Prosecution history estoppel can arise when the patentee relinquishes subject matter during the prosecution of the patent—that is, during examination of a patent application at the U.S. Patent & Trademark Office (USPTO)—either by amendment or argument. A narrowing amendment made to satisfy any requirement for patentability (under 35 U.S.C. §§ 101-103, 112, 161, or 171) may give rise to an estoppel. When it applies, prosecution history estoppel will prevent a patentee from relying on the Doctrine of Equivalents to establish infringement based on the particular equivalents surrendered. A given claim limitation might be given only its literal scope (as properly construed) but no more. This policy allows competitors to rely on prosecution history estoppel to ensure that their own devices/processes will not be found to infringe by equivalence.
The Basic Rule
The Doctrine of Equivalents is an equitable doctrine created by courts long ago. It is premised on language’s inability to capture the essence of innovation, allowing some protection beyond the literal scope of a claim where the claimed invention and the accused product or process are equivalent. Its purpose is to “temper unsparing logic” that “would place the inventor at the mercy of verbalism and would be subordinating substance to form” and it evolved in response to situations where accused infringers attempted to “practice a fraud on a patent” by introducing “minor variations to conceal and shelter the piracy.” However, there is a tension between such concerns and the need for patents to put the public on notice of what a patent does and does not cover.
Prosecution history estoppel is about interpreting patent claims by reference to the history that led to their grant. It limits the patentee’s ability to establish infringement by equivalence to help provide certainty to competitors about the enforceable scope of a U.S. patent. Accordingly, the Doctrine of Equivalents is not available where prosecution history shows the inventor was able to capture equivalent differences in words but chose narrower language. The patentee cannot later recapture what was previously surrendered under the guise of the Doctrine of Equivalents. Where the original patent application once embraced the purported equivalent but the patentee narrowed his claims to obtain the patent or to protect its validity, the patentee cannot assert that he or she lacked the words to describe the subject matter in question.
Estoppel Can Arise Through Amendment or Argument
Prosecution history estoppel can arise two ways: (1) by making a narrowing amendment to the claim (amendment-based estoppel) or (2) by surrendering claim scope through argument to the patent examiner (argument-based estoppel). These two possibilities are discussed in turn.
How Amendment-Based Estoppel Can Arise
The first way that prosecution history estoppel can arise is by way of a narrowing amendment to a claim during prosecution. The question of what constitutes a narrowing amendment will depend on the context of a particular patent claim. But a classic example is adding words that narrow the limitations of a claim to avoid a prior art reference cited in a rejection in an office action. As another example, which is less intuitive, courts have said rewriting a dependent claim in independent form is an amendment adding a new claim limitation, which constitutes a narrowing amendment that may give rise to an estoppel.
How Argument-Based Estoppel Can Arise
Argument-based estoppel arises when the prosecution history evinces a “clear and unmistakable” surrender of subject matter. Argument-based estoppel most often arises when the patentee tries to convince a patent examiner that the claims of an application recite something different from the prior art. For instance, a patentee may have argued that a claim term has a meaning that is narrow enough to avoid a disclosure or teaching in a cited prior art reference. In such a situation, the patentee will likely be estopped from later asserting that the Doctrine of Equivalents encompasses what was previously argued to be outside the scope of the claimed invention. Such arguments are treated like an acknowledgement that the patentee knew the meaning of the claim language and deliberately chose narrower language in order to obtain a patent.
Scope of the Estoppel
Though prosecution history estoppel can bar a patentee from challenging a wide range of alleged equivalents used by competitors, its reach requires examination of the particular subject matter surrendered. Even where prosecution history estoppel applies, the scope of the estoppel is not always absolute. These inquiries differ somewhat between amendment-based estoppel and argument-based estoppel.
Scope of Amendment-Based Estoppel
The scope of amendment-based estoppel depends on the claim language at issue and the reason for the amendment. For instance, where the reason for the amendment was not related to avoiding the prior art, it does not necessarily preclude infringement by equivalents of that element. But an amendment to clarify the recitation of the claimed invention to satisfy definiteness requirements for patentability would give rise to an estoppel, even though there was no prior art reference prompting the change. Also, cancellation of a claim can give rise to estoppel with regard to any claim(s) that remain (or are added). However, the reason for an amendment is often not clear from the prosecution history.
When no explanation for an amendment is provided, there is a rebuttable presumption that the Doctrine of Equivalents is not available at all. When the purpose underlying a narrowing amendment cannot be determined—and hence the rationale for limiting the estoppel to surrender of only particular equivalents—it is presumed that the patentee surrendered all subject matter between the broader and the narrower language. But that presumption of amendment-based estoppel can be overcome for a particular equivalent when (1) the equivalent in question was unforeseeable at the time of the application, (2) rationale underlying the amendment bears no more than a tangential relation to the equivalent in question, or (3) the patentee could not reasonably be expected to have described the insubstantial substitute in question.
Scope of Argument-Based Estoppel
The scope of argument-based estoppel is based on the scope of particular arguments made during prosecution. Unlike amendment-based estoppel, there is no presumption-and-rebuttal approach. Rather, the question is how far argument-based estoppel applies in the first place, if at all. The question is whether there was a clear and unmistakable argument-based surrender of particular subject matter. Courts have said that simple arguments and explanations to the patent examiner do not surrender an entire field of equivalents. But any arguments can still surrender some equivalents, even if they do not surrender all possible equivalents. This is very context-dependent. The key to this inquiry is whether a competitor would reasonably believe that the patentee’s argument had surrendered the relevant subject matter.
However, courts have said that any clear assertions made during prosecution in support of patentability, whether or not those assertions were actually required to secure allowance of a claim, may still create an argument-based estoppel. Also, once an argument is made regarding a claim term that creates an estoppel, that estoppel will apply to that term in other claims in the patent too.
Prosecution Disclaimer
Prosecution disclaimer is a separate but related concept. Rather than relating to the availability of the Doctrine of Equivalents to establish infringement, prosecution disclaimer or disavowal can limit the proper construction of a claim’s literal scope. Thus, it may affect whether or not literal infringement is found—prior to any consideration of the Doctrine of Equivalents. For example, it can arise when a patentee makes arguments during prosecution about how the pending claims differ from the prior art. This is meant to prevent patentees from opportunistically taking different (and broader) positions in court when asserting infringement than when obtaining the patent in the first place. Statements made during the prosecution of family-related applications, even later-filed ones and foreign counterparts, may sometimes result in prosecution disclaimer as well.
Questions about prosecution disclaimer pertain to proper claim construction. Claim terms are presumed to carry their full and customary meaning unless the patentee unequivocally imparted a novel meaning to those terms either in the patent application itself (called acting as her own lexicographer) or expressly relinquished claim scope during prosecution. Just as with argument-based estoppel, prosecution disclaimers must be “clear and unmistakable” in order to limit claim scope. An ambiguous statement during prosecution will not limit a claim term’s ordinary meaning.
An important difference between prosecution disclaimer and prosecution history estoppel is when they are taken into account. Prosecution disclaimer is a matter of claim construction. That is something courts do as a first step in patent infringement analyses, without reference to the specific product or process accused of infringement. In contrast, the Doctrine of Equivalents is bound up with the subsequent comparison of the accused product or process to the asserted patent claims as properly construed. Prosecution history estoppel is a question of whether a patent owner is permitted to invoke the Doctrine of Equivalents in particular ways in the second part of infringement analysis, after claim construction. But if literal infringement is found—despite any prosecution disclaimer—there is no need to reach the Doctrine of Equivalents.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
At a most basic level, patent infringement in the U.S. involves making, using, selling, offering for sale, importing into the USA a patented invention without authorization. Although there are some additional grounds for infringement that may apply in some other circumstances. All grounds for infringement fall into two general categories: direct infringement and indirect infringement. These categories refer to who is being accused and whether they are directly responsible or instead indirectly or partly responsible.
There are multiple types of infringement under each category. These include literal or Doctrine of Equivalents infringement, and, for indirect infringement, active inducement of infringement, contributory infringement, and certain activities related to components for export from the USA. Each of these provisions, set forth in § 271 of the U.S. patent laws, is taken up further below.
Direct Infringement
Direct patent infringement means that an accused party is directly responsible for infringement a patent. Direct infringement requires that each and every limitation (or element) of at least one claim of an asserted patent is met either literally or under the Doctrine of Equivalents. If a limitation of a given patent claim is not present in the accused product or process, either literally or equivalently, then that claim is not infringed.
The sorts of things that can constitute direct infringement include the following:
making (that is, manufacturing) the patented invention in the USA (35 U.S.C. § 271(a))
submitting a new drug application for U.S. regulatory approval (Hatch-Waxman Act; 35 U.S.C. § 271(e))
importing into the USA, or offering to sell, selling, or using within the USA, a product which is made outside the USA by a process patented in the USA, unless it is materially changed by subsequent processes or it becomes a trivial and nonessential component of another product (35 U.S.C. § 271(g))
violations of certain additional rights to exclude specific to plant patents (35 U.S.C. § 163)
Normally, any of these infringing acts requires a single entity to satisfy each and every limitation of a claim. However, it is also possible to have vicarious liability for infringement in situations where there are multiple entities involved in the use of a patented method/process or the making or using of a patented system/device. Vicarious liability is a type of direct infringement stemming from principles of agency law, and includes principal-agent relationships, contractual arrangements, and joint enterprises. But it does not include joint tortfeasor liability. Vicarious liability depends on control exercised by the entity accused of infringement over other involved entities. Control is what makes vicarious liability for direct infringement differ from indirect infringement (discussed below), with only the latter encompassing arms-length transactions and/or independent action.
There are two ways of finding infringement that differ in terms of how the accused product or process compares to the scope of the claim(s) of the asserted patent:
Literal Infringement
Infringement Under the Doctrine of Equivalents (also called infringement by equivalence)
Literal Infringement
Literal infringement means that the accused product or process falls within the scope of the asserted claim(s) as construed by a court. Under U.S. law, infringement analysis is a two-step process. It involves, first, construing the claims to ascertain their meaning to a person of ordinary skill in the art and to resolve any ambiguities or disputes over that meaning, and, second, comparing the accused product/process to the properly construed claim(s). Literal infringement is present when the accused infringer meets each and every limitation (or element) of an asserted patent claim exactly, as properly construed. Any deviation from a claim limitation (as properly construed) precludes a finding of literal infringement.
Infringement Under the Doctrine of Equivalents
Under the Doctrine of Equivalents, a product or process that does not literally infringe upon the express terms of a patent claim may nonetheless still be found to infringe if there is “equivalence” between the elements of the accused product or process and claimed elements of the patented invention. This type of infringement arises when the accused product or process is outside the literal scope of at least one limitation of an asserted claim, as properly construed. Patentees rely on the Doctrine of Equivalents under the second step of the infringement analysis, if at all, only if literal infringement cannot be established. Otherwise, the Doctrine of Equivalents can apply to the same set of activities as for literal infringement.
This is an equitable doctrine meant to “temper unsparing logic” that “would place the inventor at the mercy of verbalism and would be subordinating substance to form.” It evolved in response to situations where accused infringers attempted to “practice a fraud on a patent” by introducing “minor variations to conceal and shelter the piracy.” Of course, the doctrine is in tension with the policy requiring that claims put the public on notice of a patent’s scope. This is a reason the Doctrine of Equivalents is not meant to be routinely invoked and is not applied broadly. In other words, this type of infringement is a limited exception to the general rule that patent claims must reasonably put others on notice of the outermost boundaries of what constitutes infringement. Put another way, it allows a limited form of “central” claim enforcement in a regime of “peripheral” claiming.
The Doctrine of Equivalents is applied individual claim limitations rather than to the claimed invention as a whole. To find infringement, each claim limitation (or element) must be found either literally or equivalently in the elements of accused product/process. This is called the “all elements” rule. The question of equivalence is inapplicable if a claim limitation is totally missing from an accused device. The Doctrine of Equivalents cannot be used to re-draft claims and effectively eliminate limitations entirely. Though this inquiry always revolves around what differences can reasonably be considered equivalent. An undue expansion of a patent’s claim(s) is not permitted. After-arising technology can potentially be encompassed by the Doctrine of Equivalents (unlike for means-plus-function equivalents).
There are two approaches to assessing equivalents: the “insubstantial differences” test and the “function-way-result” test. The function-way-result test (also called the “triple identity” test) says that equivalence may be present for a given element if the accused product/process performs substantially the same function in substantially the same way with substantially the same result. This is not the only way to assess whether differences are insubstantial, but it is particularly useful for certain types of inventions such as mechanical devices. For biochemical inventions, however, looking at substantial differences may sometimes be more appropriate than the function-way-results test.
There are numerous limits on the Doctrine of Equivalents, which are really beyond this basic introduction. But an extremely important limit on the availability of the Doctrine of Equivalents is prosecution history estoppel. Things that the patentee did or said when obtaining the asserted patent might limit the patentee’s ability to later rely on the Doctrine of Equivalents. So the Doctrine of Equivalents is not always or automatically available.
Indirect Infringement
Indirect patent infringement means that an accused party is causing or enabling someone else to infringe. It can apply when an accused infringer meets some but not all of the limitations (or elements) of an asserted patent claim. It includes three types of infringement, which differ in terms of what the accused indirect infringer is doing:
Supplying Component for Export for Combination Outside the USA (35 U.S.C. § 271(f))
Generally speaking, there are additional requirements that must be satisfied to establish indirect infringement that are not required for direct infringement. Those additional requirements vary depending on what type of indirect infringement is asserted.
Also, relevant limitations of asserted claim(s) can be assessed under either their literal scope or under the Doctrine of Equivalents, if available—see discussions above of literal and Doctrine of Equivalents infringement for direct infringement. This is really to say that the Doctrine of Equivalents may still apply to indirect infringement scenarios.
Active Inducement of Infringement
Actively inducing someone else to infringe a patent constitutes inducement of infringement. Specifically, “[w]hoever actively induces infringement of a patent shall be liable as an infringer.” (35 U.S.C. § 271(b)). This is a form of vicarious liability. Active inducement requires taking an affirmative steps to encourage infringement by another entity, as well as knowledge that the encouraged acts infringe the asserted patent. A key component of inducement is that it requires there be at least one direct infringer. But the difference here is that instead of suing the direct infringer, a different entity is sued for inducement.
Inducement commonly arises in situations involving claims to a method of using a product. Rather than sue the end user, which may be a potential customer, the patentee instead sues a competitor making and selling products used by others to (directly) perform and infringe the asserted method claim(s). It also sometimes arises where a corporate officer or owner induces his or her company to infringe, making that individual personally liable for infringement.
Contributory Infringement
Contributory infringement arises when selling, offering to sell, or importing components that are specially made or adapted for use to infringe a patent. However, contributory infringement excludes activities involving a staple article or commodity of commerce that is suitable for substantial noninfringing use. A “substantial noninfringing use” is any use that is not unusual, far-fetched, illusory, impractical, occasional, aberrant, or experimental. So there is normally no liability for selling general-purpose commodities, even if they could be used in making or using a patented invention.
“(c) Whoever offers to sell or sells within the United States or imports into the United States a component of a patented machine, manufacture, combination or composition, or a material or apparatus for use in practicing a patented process, constituting a material part of the invention, knowing the same to be especially made or especially adapted for use in an infringement of such patent, and not a staple article or commodity of commerce suitable for substantial noninfringing use, shall be liable as a contributory infringer.”
In order for contributory infringement to be present, the infringer must know that the combination for which his component was especially designed was both patented and infringing. This knowledge requirement differentiates contributory infringement from direct infringement, which does not require any such knowledge of the patent or infringement (except to enhance damages).
Contributory infringement is important for situations involving the sale of repair or replacement parts for use in or with patented products or methods.
Supplying Component for Export for Combination Outside the USA
Section 271(f) of the patent laws creates two grounds for infringement involving activities in the USA relating to products made in a foreign country. They arise when components of a patented invention are supplied for export from the USA. These grounds for infringement are similar to yet distinct from active inducement and contributory infringement, discussed above. But these provisions do not require that the equivalent of “foreign” direct infringement occur. That is, the actual combination need not actual occur. However, these provisions apply exclusively to apparatus claims, and are not available for method/process claims. They also do not apply to activities that occur entirely outside the USA. Also, § 271(f)(1) has a quantitative requirement about the number of components involved and it does not apply to only a single component.
“(f)
(1) Whoever without authority supplies or causes to be supplied in or from the United States all or a substantial portion of the components of a patented invention, where such components are uncombined in whole or in part, in such manner as to actively induce the combination of such components outside of the United States in a manner that would infringe the patent if such combination occurred within the United States, shall be liable as an infringer.
(2) Whoever without authority supplies or causes to be supplied in or from the United States any component of a patented invention that is especially made or especially adapted for use in the invention and not a staple article or commodity of commerce suitable for substantial noninfringing use, where such component is uncombined in whole or in part, knowing that such component is so made or adapted and intending that such component will be combined outside of the United States in a manner that would infringe the patent if such combination occurred within the United States, shall be liable as an infringer.”
The grounds for infringement under § 271(f) are somewhat rarely invoked. This is largely because manufacturing costs are often higher in the USA than abroad. As a result, courts have not extensively clarified the scope and proper application of these provisions. But suffice it to say they may apply in situations where components are being produced and/or sold in the USA for export.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Intellectual property (IP) litigation tends to be relatively expensive compared to other types of lawsuits. There are many reasons for that. Though the complexity of the legal issues involved and a tendency for extensive pre-trial discovery and use of expert witnesses contribute to the total costs.
Below are graphs showing average costs through various stages of a an infringement or misappropriation lawsuit in the U.S. A summary graph compares average costs for “small” patent, copyright, trademark, and trade secret cases with less than $1,000,000 at risk. There are also individual graphs for patent, copyright, trademark, and trade secret cases with different amounts at risk, that is, with different amounts of potential damages for infringement or misappropriation (in U.S. dollars). All data comes from the 2023 AIPLA Report of the Economic Survey.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Patent marking can be important for obtaining full recovery of infringement damages. When enforcing a patent against an infringer in the United States, damages for infringement of a patented article can usually be recovered only from the date the infringer had actual or constructive notice of the patent(s), whichever comes first. Actual notice requires the affirmative communication of a specific charge of infringement by the patentee to the accused infringer, such as in a cease-and-desist letter or filing an infringement lawsuit. Constructive notice is established by the patentee properly marking patented articles, regardless of whether a particular infringer actually sees that patent notice on products.
The following is a brief overview of basic U.S. patent marking legal requirements as well as guidance about how to properly implement patent marking. A more detailed treatment (with extensive examples) is provided in the Patent Marking Guide.
The U.S. Marking Requirement
The U.S. patent laws provide the following statutory marking requirement:
“Patentees, and persons making, offering for sale, or selling within the United States any patented article for or under them, or importing any patented article into the United States, may give notice to the public that the same is patented, either by fixing thereon the word ‘patent’ or the abbreviation ‘pat.’, together with the number of the patent, or by fixing thereon the word ‘patent’ or the abbreviation ‘pat.’ together with an address of a posting on the Internet, accessible to the public without charge for accessing the address, that associates the patented article with the number of the patent, or when, from the character of the article, this can not be done, by fixing to it, or to the package wherein one or more of them is contained, a label containing a like notice. In the event of failure so to mark, no damages shall be recovered by the patentee in any action for infringement, except on proof that the infringer was notified of the infringement and continued to infringe thereafter, in which event damages may be recovered only for infringement occurring after such notice. Filing of an action for infringement shall constitute such notice.”
These statutory marking requirements apply to all types of U.S. patents: utility, design, and plant. Having a marking requirement helps to avoid innocent infringement situations, among other things.
Patent Marking Provides Constructive Notice
Marking patented articles provides constructive notice to the public that an article is patented. To be legally sufficient to establish constructive notice, the patentee must be able to prove that substantially all of the patented articles being distributed were properly marked, and that once marking was begun, the marking was substantially consistent and continuous. If marking is defective at first, curing those defects going forward is possible. But full compliance with marking requirements to provide constructive notice to infringers is not achieved until the time the patentee consistently marked substantially all of the patented products, and if marking was deficient for a time then constructive notice will not be provided unless and until proper marking occurs with subsequent sales.
Possible Exceptions to Marking Requirements
The most important exception to the marking requirement is where the patentee has not sold any patented articles. When there are no products to mark, there is no failure to mark and therefore no bar to recovery of pre-suit damages.
Additionally, because the marking statute refers only to a “patented article”, patents with method or process claims are treated differently. Neither marking (constructive notice) nor actual notice is required to obtain back damages for infringement of asserted patents having only method or process claims. For patents having both apparatus and method claims, marking might still be required (if apparatus claims are asserted) and is therefore recommended.
Licensee(s) and Other Authorized Parties Must Mark Too
Marking requirements apply not only to the patentee but anyone making, selling, or offering for sale the patented article “for or under” the patentee or importing it into the U.S. Where a patent is licensed to another, expressly or impliedly, or is the subject of a covenant not to sue or the like, the other entity is required to mark as well. Authorized activities by an outsourced manufacturer or authorized seller are treated as if they are by the patentee in terms of marking requirements in this respect. Failure of a licensee or other authorized user to consistently mark substantially all licensed products will frustrate efforts to establish constructive notice. This requirement for licensees and authorized users is subject to a rule of reason. Some instances of omitted marking by others might be excused so long as the patentee makes reasonable efforts to ensure their compliance with marking requirements. It is recommended that any license for a U.S. patent obligate the licensee to comply with marking requirements. If that cannot be done, but a part (sub-component) is sold so that an authorized downstream reseller or importer will use it to assemble a patented article, that the part specifically intended for use in the patented combination carry a “for use under” patent marking notice.
How to Implement Patent Marking: Two Possibilities
There are two ways to mark patented articles in accordance with U.S. law: physical or virtual marking.
Physical Marking
Physical patent marking (which can also be called conventional or traditional marking) involves fixing notices on the patented articles themselves in a way that associates the patented article with the number of the patent. Such a notice must include the word “patent” or the abbreviation “pat.”, together with the number of the patent.
If the nature of the patented article means such a notice cannot be fixed to the patented article itself, such as due to size constraints or where the article is a fluid or powder, the notice can instead be placed on a label fixed either to the patented article or to a package containing one or more of the patented articles. This is an alternate form of physical marking that is appropriate if (and only if) there is a legitimate reason the marking notice cannot be directly fixed to the article. And that reason should involve more than mere convenience or subjective preference.
An example of a proper physical patent marking notice (for the fictitious U.S. Pat. No. 00,000,000) would be the following fixed directly on an article covered by the claims of the indicated patent:
Pat. 00,000,000
If multiple patents apply to the same patented article, they can be listed together. It is not necessary to repeat the word “patent” or abbreviation “pat.” before each patent number in such a list. Pluralizing the word “patent” is generally fine, as is the presence of an additional word or abbreviation, such as in “patent number 00,000,000” or “pat. nos. XX,XXX,XXX and YY,YYY,YYY”. The use of “U.S. patent” or “U.S. pat.” would also be acceptable. The text of the notice should be in English.
Virtual Marking
Virtual patent marking is an acceptable alternative to physical marking. It can be useful in situations where all the patent information required to provide constructive notice cannot easily fit on the patented article or even its label, such as where there are multiple patents that apply to an article that is fairly small in size. As the number of digits in patent numbers increase, this sort of difficulty increases. Virtual marking can also be helpful in situations where different patents are associated with different products but having multiple product-specific notices is burdensome—a single notice template might be used listing a URL for a web page with patent association information for multiple products. For instance, virtual marking can help minimize the need to replace or modify molds used to create a patent marking notice directly on molded articles as new patents issue.
Implementing virtual patent marking involves fixing notices on the patented articles themselves in a way that associates the patented article with the number of the patent. Such a virtual marking notice must use the word “patent” or the abbreviation “pat.” together with an address of a posting on the Internet (that is, a web page URL), accessible to the public without charge for accessing the address.
If the nature of the patented article makes means such a notice cannot be fixed to the patented article itself, the virtual marking notice (indicating “patent” or “pat.” together with a URL) can instead be placed on a label fixed either to the patented article or to a package containing one or more of the patented articles. This is an alternate form of virtual marking that is appropriate if (and only if) there is a legitimate reason the virtual marking notice cannot be directly fixed to the article. And that reason should involve more than mere convenience or subjective preference.
An example of a proper virtual patent marking notice fixed on a patented article or its label is the following:
Pat. www.example.com/patents
The main feature of virtual patent marking is that the information associating the patented article with the number(s) of the patent(s) that cover it appears on a freely-accessible web page rather than directly on the article or its label. There is still a requirement for a notice on the patented product or its label. A marking web page, alone, is insufficient unless there is also a proper notice on the patented product or its label to direct people to that web page’s address. Moreover, a virtual marking notice on a product or its package is insufficient without an acceptable posting accessible from the identified Internet address.
The difference between physical and virtual marking really involves the manner of conveying the required association between the patent number(s) and the patented article. With traditional physical patent marking, the association is implicit in terms of which patent numbers are including in or omitted from a notice fixed to a particular product or its label. In virtual marking, the notice fixed to the product or its label merely directs the public to a web page but the web page must further provide an association between given patent(s) and the specific product(s) that practice those patent(s).
Courts have said that virtual patent marking does not allow a patentee to avoid the traditional burden of determining which patent(s) apply to specific products and indicating that patent-to-product association. The patentee cannot shift that burden to the public. A web page that presents a “research project” forcing visitors to determine patent-to-product association(s) on their own fails to provide constructive notice. Any web page lacking the required “association” between the patent(s) and patented article(s) is legally deficient and will not provide constructive notice allowing recovery of pre-suit infringement damages.
Certain courts have found the following to be insufficient for virtual marking:
A web page listing all of a company’s patents with an indication that “one or more” listed patents “may be used” by unspecified products within a stated product category (cite)
A web page listing multiple patent numbers/titles and grouping them by product category, without indicating which specific products within each category were covered by specific patents (cite)
A table on a web page listing patent numbers and titles but lacking any product information (where the company sold multiple products and one was unrelated to its patents) (cite)
Patent-to-product associations indicated somewhere other than on the virtual patent marking web page (cite)
Failing to put a notice indicating a virtual marking URL on hardware sold by a licensee that had pre-installed software that made the combined hardware-plus-software product subject to an asserted patent (cite)
False Patent Marking Prohibited
An important related concept is false patent marking. False marking generally involves marking products as patented when they are not, or marking products as “patent pending” when no patent application has been filed, with an intent to deceive. It also applies to intentional counterfeiting. Penalties apply to intentional false marking (35 U.S.C. § 292). Although the patent laws exclude from the scope of false marking the indication of an expired patent that once applied to the marked product. Also, there is no liability for honest mistakes about whether or not a patent applies.
It is important to only use patent marking where there is a reasonable basis to believe that the product is covered by the indicated patent(s). Patents that do not apply to a given product must not be marked on it (consider also any invalidation or cancellation of a given patent for continued marking). In the virtual marking context, patent-to-product associations must be specific enough to avoid false marking. Imprecise, blanket statements on virtual marking web pages implicating multiple patents and multiple products might give rise to false marking if done for purposes of deceiving the public about which patents, if any, apply to particular products. More generally, avoid marking products with any “patented” language that is confusing, geographically vague, or misleading with respect to that product’s patent status in the USA.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
There are many situations where it is desirable to challenge the validity or patentability of a granted patent or pending patent application. For instance, an invalidity search can be useful for an invalidity opinion to mitigate infringement liability, an invalidity defense in litigation, a proactive challenge to patentability at the U.S. Patent & Trademark Office (USPTO), or a pre-issuance submission (observations) to try to restrict or prevent a patent from being issued. But what is the best timing for such an invalidity search?
In one sense, an invalidity search is never strictly legally required. Though, practically speaking, invalidity searches are often crucial to avoiding or reducing liability for patent infringement in many contexts. These searches must be performed in a timely manner to obtain the greatest value from them. That includes performing searches in time to meet deadlines that require having suitable search results available.
Patent invalidity searches are reactive in the sense of being conducted in response to some infringement risk arising. That could be the receipt of a cease & desist letter, the filing of an infringement lawsuit against you, or other knowledge of a potentially problematic patent (e.g., via a freedom-to-operate study). In any event, an invalidity search requires first knowing which patent is the subject of the invalidity search. That is because an invalidity search depends on the scope of the particular claim(s) of concern and their effective filing date(s)—including any priority date(s).
It is a best practice to consider an invalidity search after a tangible risk of patent infringement comes to your attention. Knowledge of a patent coupled with a reasonable belief that infringement might be present can potentially give rise to enhanced damages for infringement. And knowledge of a pending patent application can potentially give rise to so-called “provisional rights” to pre-issuance infringement damages.
There may be deadlines that determine when invalidity search results are needed. For instance, in patent litigation in a district court, the court will issue a scheduling order that often sets a deadline to set for invalidity contentions. In is necessary to have search results available in order to formulate those invalidity contentions and prepare a suitable report. Other times, invalidity contentions might be requested through discovery requests, such as interrogatories. Either way, it is crucial to perform the invalidity search far enough in advance of such deadlines to allow for subsequent legal analysis of the search results.
Moreover, there are situations where a proactive challenge to a granted patent is desired. Proceedings such as inter partes review (IPR), post-grant review (PGR), oppositions, and the like may have various different deadlines by which a challenge must be filed. Such deadlines drive the timeline for completing invalidity searching. Just as in litigation, the search must be completed with time to spare to allow for legal analysis and preparation of any formal filing papers for the patent challenge, which may require considerable effort to prepare. Additionally, a pre-issuance submission (or observation) might be filed against a pending patent application and there likewise are both formal and practical deadlines to do so.
Lastly, if an opinion of counsel setting forth grounds for liability is desired to mitigate potential infringement damages, such an opinion should ideally be obtained before your relevant product (or process) is commercially launched. If patent in question is discovered only later, then such an opinion should be obtained without unreasonable delay. Having invalidity search results is a prerequisite to completing an invalidity opinion.
In all these possible settings, it is common for multiple invalidity searches to be performed. That can include follow-on invalidity searches performed in an iterative manner, in order to exhaustively locate prior art and to try to obtain sufficient prior art for desired (and reasonable) invalidity arguments as those arguments evolve and develop. It may also include searches performed by different searchers in different databases (including in non-patent literature databases), in different native languages, though investigation of prior public use and on-sale activities, and the like.
Have an invention you would like to patent? Have a brand you would like to register as a trademark? Concerned about infringing someone else’s intellectual property? Is someone else infringing your IP? Need representation in an IP dispute? Austen is a patent attorney / trademark attorney who can help. These and other IP issues are his area of expertise. Contact Austen today to discuss.
Is it possible for a U.S. design patent claim to include a negative limitation? It does not appear that courts have explicitly addressed this question. That is partly due to emphasis on design patent claims and infringement analyses revolving around the design as a whole, which can lead to rather conclusory decisions. But the question posed here is whether a claimed ornamental design as a whole can contain within it one or more “negative limitations” that effectively indicate the absence of some ornamental aspect, as opposed to indicating the positive (or affirmative) presence of an ornamental aspect. Certain past cases have touched on similar issues without specific reference to “negative limitations” in the sense that term is used with regard to utility patent claims.
Consider a design patent claim that shows as part of the overall ornamental design a flat surface, that is, a solid planar surface that is plain and uninterrupted. Does such a depiction include a negative limitation of sorts that excludes the presence of ornamentation on the surface? That is, does it give rise to a potentially significant overall difference when comparing a perforated surface or a surface that has substantial non-planar texturizing surface ornamentation? The same questions might arise, for instance, when a claimed design depicts only a single element (such as a single rounded corner, single support bar, single hole, etc.) but the accused product includes more than one of those elements.
In general, design patent infringement analysis involves two steps: (1) claim construction and (2) comparison of the properly construed claim to the accused product. Elmer v. ICC Fabricating, Inc., 67 F.3d 1571, 1577 (Fed. Cir. 1995). Theoretically, at least, questions about “negative limitations” in design patents could potentially arise in either of those two steps.
While, certainly, a jury can always reach an ultimate infringing/non-infringing conclusion, in the binary sense, based on the particular and specific facts at hand in any given case. But the topics at hand here are how courts should treat the legal issues surrounding how a finder of fact might be presented with design patent infringement questions where negative limitation issues are present, and also how courts making dismissal (Rule 12(b)(6)), summary judgment, judgment on the pleadings, judgment as a matter of law (JMOL), or appeal decisions can explain their reasoning under the ordinary observer test when negative limitations may be present.
Negative Limitations in Design Claim Construction
Design patent infringement analysis begins with claim construction. Although claim construction is also the first step in utility patent infringement analysis, design patent claim construction differs from that for utility patents in some important ways.
A patentable design “gives a peculiar or distinctive appearance to the manufacture, or article to which it may be applied, or to which it gives form.” Gorham Co. v. White, 81 U.S. (14 Wall.) 511, 525 (1871); see also Samsung Elecs. Co., Ltd. v. Apple Inc., 580 U.S. ___, 137 S. Ct. 429, 432-33 (2016). This means design patent claim construction must be adapted to the pictorial setting. Crocs, Inc. v. Int’l Trade Comm’n, 598 F.3d 1294, 1302 (Fed. Cir. 2010). In that sense, the Federal Circuit has said that “[d]epictions of the claimed design in words can easily distract from the proper infringement analysis of the ornamental patterns and drawings.” Id.; see also Dobson v. Dornan, 118 U.S. 10, 14 (1886) (a claimed design “is better represented by the photographic illustration than it could be by any description, and a description would probably not be intelligible without the illustration.”).
The Federal Circuit has cautioned that detailed verbal claim constructions increase “the risk of placing undue emphasis on particular features of the design and the risk that a finder of fact will focus on each individual described feature in the verbal description rather than on the design as a whole.” Egyptian Goddess, Inc. v. Swisa, Inc., 543 F.3d 665, 680 (Fed. Cir. 2008) (en banc). For such reasons, the level of detail to be used in describing the claimed design is a matter within a court’s discretion, and a court is not obligated to issue a detailed verbal description of the design if it would not be helpful. Id. at 679-80. Yet a court may use claim construction to help guide the fact finder through issues that bear on claim scope. Id. at 680.
Although not always at issue in every case, design patent claim construction can address prosecution history estoppel and prosecution history disclaimer. See Egyptian Goddess, 543 F.3d at 680. In general, the doctrine of prosecution history estoppel prevents a patentee from “recaptur[ing] in an infringement action the very subject matter surrendered as a condition of receiving the patent.” Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., Ltd., 535 U.S. 722, 734 (2002). It requires that “the claims of a patent be interpreted in light of the proceedings in the [US]PTO during the application process.” Id. at 733. The Federal Circuit has specifically held that prosecution history estoppel applies to design patents too. Pac. Coast Marine Windshields Ltd. v. Malibu Boats, LLC, 739 F.3d 694, 702 (Fed. Cir. 2014).
However, for design patents, unlike with utility patents, “the concepts of literal infringement and equivalents infringement are intertwined.” Id. at 700-01. Because it is the drawings of the design patent that provide the description of the invention, courts “look at the requisite drawings in design patents to determine whether a surrender has occurred.” Id. at 702. Estoppel arises when a narrowing amendment is made to satisfy any requirement to secure the grant of the patent, including amendments to avoid prior art or resulting from a restriction requirement. Id. at 703-04; see also Advantek Marketing Inc. v. Shanghai Walk-Long Tools Co., 898 F.3d 1210, 1216-17 (Fed. Cir. 2018).
In the Pacific Coast Marine Windshields case, a design application (for U.S. Des. Pat. No. D555,070) originally included drawings depicting—and claiming—multiple embodiments of a boat windshield. As reproduced below, the various originally-claimed embodiments showed the claimed windshield design with different vent hole configurations and also showed claimed designs that included and excluded a hatch on the front of the windshield. The examiner issued a five-way restriction requirement, identifying five distinct groups of designs as windshields with:
four circular holes and a hatch (FIG. 1);
four circular or square holes and no hatch (FIGS. 7 and 12);
no holes and a hatch (FIG. 8);
no holes and no hatch (FIG. 9); and
two oval or rectangular holes and a hatch (FIGS. 10 and 11).
In that sense, the examiner indicated that many of the different embodiments (but not all of them) represented different design inventions. In response, the patentee removed alternate embodiments, thus deleting those alternate embodiments from the scope of the claim. That prosecution history had significant implications to the scope of the claim in the granted design patent before the court (D555,070). Incidentally, the patentee chose to file only one subsequent divisional application to the “no holes and a hatch” embodiment (that became U.S. Des. Pat. No. D569,782), apparently without pursuing any other of the original alternate embodiments—though a continuation application (that became U.S. Des. Pat. No. D593,024) based off the divisional was also later filed for a partial design to only the vertical corner posts with no vent holes (with the windscreen portions unclaimed, thus potentially avoiding hatch vs. no hatch questions).
Noting that treatises and prior district court decisions had said similar things in the past, the Federal Circuit ruled that surrender of claims to the alternate designs was for reasons of patentability that caused prosecution history estoppel to attach. Pac. Coast Marine Windshields, 739 F.3d at 702-04. However, because the accused windshield product’s design had three vent holes (see above) but the patented design had four vent holes (see FIG. 1 above) and the surrendered embodiments/designs had only two vent holes (see original FIGS. 10 and 11 above), summary judgment of non-infringement was reversed and the case was remanded to the district court for further proceedings. Id. at 704-05. In other words, without reaching a definitive infringement/non-infringement decision, the patentee was barred from arguing that the design patent’s claim covered a two-hole design (or any other surrendered embodiments) but was still able to argue that a three-hole design might be covered because there was no surrendered three-hole embodiment in the original drawings. (The Federal Circuit decision did not address potential differences in the horizontal/angled frame or trim aspects of the accused design as part of the overall appearance analysis). After remand, and denial of subsequent summary judgment cross motions (which included inventorship disputes, and non-patent issues), the parties eventually settled.
Generally similar negative limitation issues have arisen in utility patent cases. For example, the Spine Solutions case involved questions of claim construction and prosecution history estoppel for a utility patent. Claim 1 of the patent in question recited “a single anchor on each of the upper surface of the upper part and the lower surface of the lower part . . . .” The relevant claim construction implicitly regarded the “single anchor” recitation as including a negative limitation, that is, requiring one anchor having the recited characteristics but excluding the presence of more than one anchor. There was no infringement by the accused device, which had two anchors rather than a “single” anchor as claimed. The Federal Circuit reasoned as follows:
“We agree with [the accused infringer] Medtronic that the court erred in determining that [the accused] O-Maverick [device] literally infringes claims 1 and 2. The [district] court construed ‘single anchor’ to mean, in relevant part, that ‘[t]he upper and lower surfaces of the implant each have one anchor having the characteristics recited in the last paragraph of [claim 1].’ Claim Construction Order, 2008 WL 4831770, at *14, 2008 U.S. Dist. LEXIS 116648, at *43 (emphasis added). A simple observation of [the accused] O-Maverick [device] confirms that the implant has two anchors on each of the upper and lower pieces, not one. The anchors are separated by a one-millimeter gap that extends all the way to the base of the implant; at no point are the two anchors joined or connected in any way. O-Maverick clearly has two anchors on each piece, not a ‘single anchor’ as recited by claims 1 and 2. Therefore, we hold as a matter of law that [the accused] O-Maverick [device] does not literally infringe claims 1 and 2.
“During prosecution, applicants expressly distinguished the claimed invention over the ‘477 patent by asserting that ‘a reference disclosing two anchors does not disclose a device affirmatively claiming a single anchor… reciting a negative limitation in the form of a single element is not disclosed by prior art which teaches more than one element.’ J.A. 17524. This is a clear disclaimer of claim scope, and prosecution history estoppel therefore bars [the patentee] SSI from arguing that a two-anchor device is equivalent to the claimed implant. Because we hold that [the accused] O-Maverick [device] is a two-anchor device, SSI cannot argue that O-Maverick infringes claims 1 and 2 under the doctrine of equivalents.”
What all these cases emphasize is that negative limitations can be at issue for design patent claim constructions, just as in utility patent cases. Prosecution disclaimer or prosecution estoppel issues resulting from arguments or amendments to a design application are especially relevant here. The Pacific Coast Marine Windshields case illustrates how those issues should be assessed as part of a design claim construction, if and when they arise. Other cases also indicated how this can be significant with respect to words in the design patent claim — such as words in the title that restrict the scope of the claim to a particular article of manufacture. Curver Luxembourg, SARL v. Home Expressions Inc., 938 F.3d 1334, 1340 (Fed. Cir. 2019); In re SurgiSil, L.L.P., No. 2020-1940 (Fed. Cir. Oct. 4, 2021). It is possible a design patent might include words like “individual” in the title that could include a negative limitation.
What is less certain for design patent claim construction is what role, if any, negative limitations have when the feature in question is something that appears in a drawing but there was no prosecution history disclaimer or estoppel. Because detailed design claim constructions that translate visual depictions into words are disfavored, it would not be appropriate in most situations to single out a particular visual element and explicitly construe it as containing a negative limitation (in the absence of a disclaimer or estoppel). That would depart from the context of the ordinary observer analysis and the requisite visual analysis of the overall appearance of the ornamental design.
Yet there may be instances where a negative limitation appears in relation to functional features, for example. The Federal Circuit has held that a claim construction may help the fact finder “distinguish[] between those features of the claimed design that are ornamental and those that are purely functional.” Egyptian Goddess, 543 F.3d at 680 (citing OddzOn Prods., 122 F.3d at 1405). A design may contain both functional and ornamental elements, even though the scope of a design patent claim “must be limited to the ornamental aspects of the design.” Ethicon Endo-Surgery, Inc. v. Covidien, Inc., 796 F.3d 1312, 1333 (Fed. Cir. 2015). “Where a design contains both functional and non-functional elements, the scope of the claim must be construed in order to identify the non-functional aspects of the design as shown in the patent.” OddzOn Prods., 122 F.3d at 1405; accord Ethicon Endo-Surgery, Inc., 796 F.3d at 1333. This ensures that the claim is limited to the ornamental aspects of the design, and does not extend to “the broader general design concept.” OddzOn Prods., Inc., 122 F.3d at 1405; see also Read Corp. v. Portec, Inc., 970 F.2d 816, 825 (Fed. Cir. 1992) (“[w]here . . . a design is composed of functional as well as ornamental features, to prove infringement a patent owner must establish that an ordinary person would be deceived by reason of the common features in the claimed and accused designs which are ornamental.”). But a construction of design features that are only partly functional, with some at least minimal ornamentation, must not entirely eliminate whole aspects from the scope of the claim, even as the functional elements limit and narrow the claim scope. See Sport Dimension, Inc. v. Coleman Co., Inc., 820 F.3d 1316, 1322-23 (Fed. Cir. 2016); Apple Inc. v. Samsung Elecs. Co., Ltd., 786 F.3d 983, 998-99 (Fed. Cir. 2015).
Negative Limitations in Comparisons Between Claimed Design and Accused Product
Following claim construction, if any, the design patent’s claim as construed is compared to the allegedly infringing products. Elmer, 67 F.3d at 1577. When considering infringement of a design patent, the “ordinary observer” test is the sole test for determining if infringement has occurred. Egyptian Goddess, 543 F.3d at 678 (rejecting the use of a separate “point of novelty” test); Crocs, 598 F.3d at 1303. Under the ordinary observer test, infringement occurs:
“if, in the eye of an ordinary observer, giving such attention as a purchaser usually gives, two designs are substantially the same, if the resemblance is such as to deceive such an observer, inducing him to purchase one supposing it to be the other, the first one patented is infringed by the other.”
Gorham, 81 U.S. at 528; Egyptian Goddess, 543 F.3d at 670-71.
This test has been codified in the patent laws, which provide as follows:
“Whoever during the term of a patent for a design, without license of the owner, (1) applies the patented design, or any colorable imitation thereof, to any article of manufacture for the purpose of sale, or (2) sells or exposes for sale any article of manufacture to which such design or colorable imitation has been applied shall be liable to the owner to the extent of his total profit, but not less than $250, recoverable in any United States district court having jurisdiction of the parties.”
35 U.S.C. § 289
Thus, as the ordinary observer test is sometimes described, infringement is not found unless the accused article embodies the patented design or any colorable imitation of it. Egyptian Goddess, 543 F.3d at 678 (citations omitted). Though recall that for design patents “the concepts of literal infringement and equivalents infringement are intertwined.” Pac. Coast Marine Windshields, 739 F.3d at 700-01.
Against that backdrop, the question of potential negative limitations can arise in the context of whether logos (or the like) present on the accused product can or should be considered when comparing it to the design patent claim to determine if there is infringement.
It is necessary to compare the claimed design (as construed) as a whole to accused product. Ethicon Endo‐Surgery, 796 F.3d at 1335; Crocs, 598 F.3d at 1302-06. This is to say that in the “ordinary observer” analysis, the patented design is viewed in its entirety, as it is claimed. L.A. Gear, Inc. v. Thom McAn Shoe Co., 988 F.2d 1117, 1125 (Fed. Cir. 1993). “[A]ll of the ornamental features illustrated in the figures must be considered in evaluating design patent infringement.” Contessa Food Prods., 282 F.3d at 1378. “A patented design is defined by the drawings in the patent, not just by one feature of the claimed design.” KeyStone Retaining Wall Sys., 997 F.2d at 1450. This means the comparison of the claimed design (as construed) to the accused product must generally include all of the patent figures in comparison, and it cannot merely compare separate elements in isolation or involve serial element-by-element comparison.
Yet an infringement analysis that recites significant differences between the ornamental features of the claimed and accused designs is still acceptable if, in determining infringement, that analysis still mainly focuses on whether an ordinary observer would be deceived into thinking that the accused product’s design was the same as the patented design. Richardson v. Stanley Works, Inc., 597 F.3d 1288, 1295-96 (Fed. Cir. 2010). It is in that sense that negative limitations can be used to help articulate significant differences from the standpoint of an ordinary observer.
Along those lines, the Federal Circuit has held that the finder of fact can consider “an ornamental logo, its placement, and its appearance as one among other potential differences between a patented design and an accused one.” Columbia Sportswear N. Am., Inc. v. Seirus Innovative Accessories, Inc., 942 F.3d 1119, 1131 (Fed. Cir. 2019). In a subsequent August 2021 trial under that guidance, a jury found no infringement. Columbia Sportswear N. Am., Inc. v. Seirus Innovative Accessories, Inc., No. 3:17-cv-01781 (S.D. Cal. Aug. 6, 2021) (jury verdict of non-infringement). The parties subsequently cross appealed.
In Columbia, the patent owner sometimes made a comparison of only a selected portion of the claimed design to the accused product in briefing. This had the effect of broadening the asserted claim. For instance, in the first comparative example below for district court summary judgment briefing, note how the claimed design uses broken lines in FIG. 1 to show that a boundary exists but is unclaimed (seeMPEP § 1503.02(III) (9th Ed., Rev. 10.2019, June 2020)). But the claimed design of FIG. 1 includes a generally sinusoidal wave pattern with four full crests and five full troughs that appear uninterrupted between the broken line boundaries; whereas in a comparison table used in briefing only part of the claim with merely three full (and uninterrupted) crests and troughs was reproduced as allegedly being the “Patented Design”. And in the second example below, from appellate briefing, note how FIG. 2 is used by the patentee for comparison despite the asserted design patent stating that “FIG. 2 is an enlarged elevational view thereof, taken from any area in the design” (that is, FIG. 2 merely shows an enlargement of a portion [with]in the claimed design but does not show the entire claimed design). If we analogize this to the utility patent context, it is like comparing a selected claim limitation to the accused product in isolation without addressing one or more additional limitations present in the claim. The significance of the accused product’s interruption (with repeating logos) in comparison to the claimed uninterrupted design was a key issue in the case including its appeals. So the question of what constitutes the full scope of the claimed design is foundational to what is or is not interrupted in the accused product.
FIG. 1 of U.S. Des. Pat. No. D657,093 (left) and Portion of Plaintiff Columbia’s March 7, 2016 Motion for Partial Summary Judgment (right)Portion of U.S. Des. Pat. No. D657,093 (left) and Portion of Plaintiff Columbia’s September 18, 2018 Appellate Response and Reply Brief Showing FIG. 2 of U.S. Des. Pat. No. D657,093 Overlaid on Photo of Accused Product (right)
The district court declined to construe the design patent claim with a detailed verbal description in its Markman order, or to provide any other construction or guidance about design patent conventions, but instead later provided jury instructions that stated:
“A design patent’s claim defines what is covered by the patent. The claim is typically represented by illustrations. It is permissible to illustrate more than one embodiment of a design in a single design patent application. Each design patent contains multiple drawings to illustrate the claimed design.
The scope of the claim encompasses the design’s visual appearance as a whole. It does not cover a general design concept and is not limited to isolated features of the drawings. An inventor’s subjective intent is not relevant to the scope of the claimed design”
Quote from Jury Instruction No. 9 (as filed Aug. 6, 2021)
That jury instruction (No. 9) was largely generic. It could have been issued in any design patent case without changing a word. Neither the jury instruction nor the Markman order specifically addressed the proper interpretation of the language describing FIG. 2 quoted above, which is part of the claim. Most significantly, the jury was not instructed to disregard the presence of logos on the accused product (as Columbia had sought). But, additionally, the jury was not instructed about whether the asserted design patent actually included multiple embodiments or whether certain drawings showed the same design or merely incomplete portions of it. That meant that, in the Columbia case, there was no express “negative limitation” claim construction. Instead, everything came down to the comparison of the overall appearances.
“To determine infringement of a design patent, you must compare the overall appearances of the accused design to the Design Patent. The accused design is Seirus’s HeatWave fabric. If you find by a preponderance of the evidence that the overall appearance of the accused design is substantially the same as the overall appearance of the Design Patent, you must find that the accused design infringed the Design Patent.
Two designs are substantially the same if, in the eye of an ordinary observer, giving such attention as a purchaser usually gives, the resemblance between the two designs is such as to deceive an ordinary observer, inducing him to purchase one supposing it to be the other. You do not need, however, to find that any purchasers were actually deceived or confused by the appearance of the accused products. You should consider any perceived similarities or differences between the patented and accused designs. Minor differences should not prevent a finding of infringement.”
Quote from Jury Instruction No. 10 (as filed Aug. 6, 2021)
The jury instruction (No. 10) regarding the comparison step did mention the accused product by name. But otherwise that instruction is also fairly generic. Jury instructions nos. 11-13 also pertained to design-patent-specific issues, including comments about the proper use of prior art in instruction no. 11.
The district court could have provided further claim construction guidance. But it chose not to. As already noted, the jury held that the patented design was not infringed. On the next appeal, there will surely be a dispute over the ultimate verdict of non-infringement of the design patent, but also perhaps about the mostly generic jury instructions related to design patent claim construction and infringement analysis and how those impact any “negative limitations” in the design patent claim. Though, interestingly, at the district court neither party really argued this point regarding the proposed final jury instructions for the August 2021 trial (most of the arguments over those instructions instead centered around what could be ignored, proper consideration of marketing materials evidence, how functionality should be referenced if at all, and the relevance and proper role of alleged prior art).
Conclusion
The appropriate way to address “negative limitations” in design patent claims is: first, to address in claim construction any prosecution history disclaimer or prosecution history estoppel issues that might give rise to recapture issues around such “negative limitations”, as well as any relevant interpretations of the text of the claim (including the title and description) that might do the same; and, second, to articulate the way design features affirmatively present in the accused design represent significant differences from such “negative limitations” in the claimed design in an analysis that still mainly focuses on whether an ordinary observer would be deceived into thinking that the accused product’s design was the same as the patented design overall.
The first aspect might not be relevant in all cases. Those questions will be highly dependent on the content of the asserted design patent claim and the prosecution history. But the second aspect could potentially apply whenever the asserted design patent appears to recite, in part, a “negative limitation”. This second part might impact jury instructions, as well as the way a case is argued to the finder of fact. It could also impact a pre-suit opinion of counsel analysis. Both factors might come up as part of dismissal, summary judgment, judgment on the pleadings, and/or JMOL motions, as well as in appeals.
January 2022
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
It may be desired to proactively challenge the validity or patentability of a granted U.S. patent for a variety of reasons. What are the available options to challenge a granted patent either at the U.S. Patent & Trademark Office (USPTO) or in court? The following table compares the different types of proceedings and summarizes the applicable standards.
Anyone with standing (substantial controversy between parties having adverse legal interests of sufficient immediacy and reality; requires affirmative act by patentee)
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
The Scope and Limits of Trade Dress and Patent Protection in Product Shapes: Food Product Case Studies
Intellectual property (IP) protection for product configurations of comestibles, confections, foodstuffs, and the like have been a matter of dispute in courts for well over a century. A variety of distinct IP rights may be invoked in this context, among them design patents and trade dress (either as a registered or unregistered trademark). Courts have grappled with the limits of such IP rights, seeking to prevent end-runs around the expiration of patent and copyright rights that the U.S. Constitution restricts to only limited times.[i] Such limits on IP rights embody long-standing Anglo-American legal principles in place since the Statute of Monopolies curbed the English Crown’s practice of granting “odious” monopolies over common commodities to raise funds or bestow favor.[ii] Cases up to the present highlight continued aggressive assertions of trade dress rights by foodstuff manufacturers—coupled with pushback by courts to deny trade dress rights in purely functional product configurations.
A number of important historical decisions observed the tendency for assertions of trade dress in (food) product configurations/shapes/forms/designs—these terms being used somewhat interchangeably—to inappropriately extend monopoly protections after a patent expired. Judge Learned Hand authored Shredded Wheat Co. v. Humphrey Cornell Co., which dealt with alleged trade dress infringement of the shape of shredded wheat biscuits after the expiration of a design patent to the same biscuit shape.[iii] He wrote that “the plaintiff’s formal dedication of the design [upon expiration of U.S. Des. Pat. No. 24,688] is conclusive reason against any injunction based upon the exclusive right to that form, however necessary the plaintiff may find it for its protection.”[iv]
Later, the Supreme Court weighed in on a dispute between Kellogg and Nabisco, finding the pillow shape of a shredded wheat biscuit to be functional because “the cost of the biscuit would be increased and its high quality lessened if some other form were substituted for the pillow-shape.”[v] The Court stated,
“The plaintiff has not the exclusive right to sell shredded wheat in the form of a pillow-shaped biscuit — the form in which the article became known to the public. That is the form in which shredded wheat was made under the basic [utility] patent [U.S. Pat. No. 548,086]. The patented machines used were designed to produce only the pillow-shaped biscuits. And a design patent [U.S. Des. Pat. No. 24,688] was taken out to cover the pillow-shaped form. Hence, upon expiration of the patents the form . . . was dedicated to the public.”[vi]
Kellogg has remained the touchstone for cases on the limits of trade dress protection, and not just for foodstuffs. Subsequent decisions have elaborated on the non-functionality doctrine without changing the basic framework.[vii]
In a more modern case, Sweet Street Desserts, a “Blossom Design” for a round, single-serving, fruit-filled pastry with six folds or petals of upturned dough was held to be functional and, accordingly, unprotectable as trade dress because the product’s size, shape, and six folds or petals of upturned dough were all essential to the product’s ability to function as a single-serving, fruit-filled dessert pastry.[viii] Only incidental, arbitrary, or ornamental product features that identify the product’s source are protectable as trade dress. Chudleigh’s trade dress Reg. No. 2,262,208 was cancelled.[ix]
In Ezaki Glico v. Lotte, the non-functionality requirement was assessed in connection with Ezaki Glico’s POCKY® treats—thin, rod- or stick-shaped cookies partially coated in chocolate (with optional nuts)—and Lotte’s competing PEPERO® treats.[x]
Ezaki Glico’s trade dress Reg. Nos. 1,527,208 (left) and 2,615,119 (right)Photos of original (left) and album (right) PEPERO® treats (for scale, these are about the size of a medium-length bamboo cooking skewer)
The core dispute was how to define “functional” for product configuration trade dress. Ezaki Glico argued a narrow reading, equating “functional” with “essential.” The court disagreed, reading Supreme Court precedent to say that product configuration features need only be useful to be functional. That is, a product shape feature is “useful” and thus “functional” if the product works better in that shape, including shape features that make a product cheaper or easier to make or use. The 3rd Circuit held that a product feature being “essential to the use or purpose of the article or if it affects the cost or quality of the article”[xi] is merely one way to establish functionality.[xii] A product feature is also unprotectably functional if exclusivity would put competitors at a significant, non-reputation-related disadvantage.[xiii] The rejection of a narrow reading of the functionality doctrine echoes cases in other circuits characterizing the Supreme Court’s TrafFix case as setting forth two ways to establish functionality.[xiv] There are several ways to establish functionality that are not limited to merely “essential” product features.
Functionality in the trade dress context is commonly assessed through the following types of non-dispositive evidence, as summarized in Ezaki Glico:
“First, evidence can directly show that a feature or design makes a product work better…. Second, it is ‘strong evidence’ of functionality that a product’s marketer touts a feature’s usefulness. Third, ‘[a] utility patent is strong evidence that the features therein claimed are functional.’ Fourth, if there are only a few ways to design a product, the design is functional. But the converse is not necessarily true: the existence of other workable designs is relevant evidence but not independently enough to make a design non-functional.”[xv]
There was evidence of practical functions of holding, eating, sharing, or packing the POCKY treats. Ezaki Glico’s internal documents showed a desire to have a portion of the stick uncoated by chocolate to serve as a handle. The court also noted how the size of the sticks allowed people to eat them without having to open their mouths wide and made it possible to place many sticks in a package. Ads for POCKY treats also emphasized the same useful features. Ezaki Glico proffered nine examples of partially chocolate-coated treats that do not look like POCKY treats, but the court found that evidence insufficient to avoid the conclusion that every aspect of POCKY treats is useful.
Finally, the court concluded that Ezaki Glico’s utility patent U.S. Pat. No. 8,778,428 for a “Stick-Shaped Snack and Method for Producing the Same” was irrelevant. The court’s rationale for that conclusion, however, is rather unconvincing. The utility patent was applied for in 2007, with a 2006 Japanese priority claim, which was long after Ezaki Glico began selling POCKY treats in the U.S. in 1978, and also long after Lotte began selling the accused PEPERO treats in 1983 and the first explicit allegations of misconduct in 1993. That patent was also still in force (i.e., unexpired). The utility patent corresponded to an “ultra thin” version of POCKY treats and Ezaki Glico argued that its patent addressed only one of many embodiments covered by its trade dress.
The lower court discussed utility patent disclosures regarding stick warping formulated like a problem-solution statement[xvi]—somewhat akin to inventive step (obviousness) analyses in European patent practice. But unmentioned was how the patent’s disclosed stick holder necessarily produces a partial chocolate coating.[xvii] The 3rd Circuit’s reasoning about the irrelevance of the utility patent is superficial to the point of being mere tautology. The appellate opinion did not address Kellogg’s statement that the form in which a food article was made under an expired “basic” patent was relevant to trade dress eligibility or other circuits’ cases that deemed a prior manufacturing method patent to be relevant. Moreover, the court did not address the way mere descriptiveness of just one good bars registration of a trademark for an entire group of goods encompassing additional, different goods.[xviii] Whether a later-filed patent can ever provide grounds to cancel an earlier trade dress registration for functionality is a question the court essentially avoided deciding.
Something else not discussed in Ezaki Glico was the 3rd Circuit’s decision nearly a century ago in the Eskimo Pie case.[xix] There, the validity of U.S. Pat. No. 1,404,539 on the original ESKIMO PIE® chocolate-covered ice cream treat was at issue. The court held the utility patent invalid, reasoning with regard to claim 6 (in which the core and casing form a “substantially rectangular solid adapted to maintain its original form during handling”) that “[t]here is no invention in merely changing the shape or form of an article without changing its function except in a design patent.”[xx] The rectangular solid shape was found non-functional and therefore unable to distinguish the prior art in a utility patent claim. The lower court had already pithily reached these same conclusions:
“The gist of the invention, if there be one, is in sealing a block of ice cream in a sustaining and self-retaining casing of chocolate. A rectangular piece of ice cream is coated with chocolate…. All that the patentee does is to take a small brick of ice cream and coat it with chocolate, just as candies are coated. [In the prior art,] Val Miller took a round ball of ice cream and coated it, just as candies are coated. In one case the ice cream is round in form, and in the other case it is rectangular. In both cases there is a sustaining and self-retaining casing, sealing the core of ice cream…. There is no invention in form alone.”[xxi]
U.S. Pat. No. 1,404,539
In a fascinating Wired article from 2015, Charles Duan located correspondence with the inventor’s patent attorney and other pertinent historical information in museum archives.[xxii] Duan highlighted how the invention, if anything, was really about the particular formulation of chocolate that allowed it to work effectively as a coating on a frozen ice cream treat, while the patent contains no disclosure in that regard and its claims were intended to be preemptive.[xxiii] Invalidation of the ESKIMO PIE patent opened the door for the KLONDIKE® ice cream treat, introduced in 1928, which was later the subject of an 11th Circuit trade dress case about product packaging (as opposed to product configuration) for a wrapper with a pebbled texture, images of a polar bear and sunburst, bright coloring, and square size that, in combination, were held non-functional.[xxiv]
Courts have tended to be more lenient on (food) packaging trade dress when it comes to functionality.[xxv] This held true when the 11th Circuit later found the unregistered product design of DIPPIN’ DOTS® multi-colored flash-frozen ice cream spheres/beads to be functional and thus ineligible for trade dress protection.[xxvi] An unexpired utility patent (U.S. Pat. No. 5,126,156)—later held invalid and unenforceable[xxvii]—was specifically cited as evidence of functionality of the product design, along with judicial notice that certain colors connote ice cream flavor.[xxviii]
So, in 1929, the 3rd Circuit ruled that the configuration of an ESKIMO PIE treat was ornamental and non-functional, and therefore unpatentable in a utility patent; whereas, in 2021, the Third Circuit ruled that the configuration of a POCKY treat was functional, and therefore ineligible for trade dress protection. How can these decisions be reconciled?
The only way to square these cases is to say that “functionality” in the trade dress context means something legally different than in the patent context. So, an ice cream treat’s shape/configuration was insufficiently functional to support a utility patent claim though a cookie treat’s shape and configuration was too functional (useful) to support trade dress protection. But courts and other commentators often stop well short of explaining why “functionality” differs in these two contexts, or what specific evidence would differ—aside from the separate need to prove inherent or acquired distinctiveness to establish trade dress rights.[xxix]
The ultimate conclusions in the two cases, however, are very consistent in seeking to limit overreaching IP assertions. The functionality doctrine for trade dress has long been used to scrutinize attempts to secure a potentially perpetual trademark monopoly on product feature(s) thatconsumers desire in the product itself apart from any unique but optional source-identifying function(s) of product configuration—as well as manufacturers’ concerns about ease and cost of manufacturability. In the patent context, utility requirements at least implicitly revolve around the technological arts rather than aesthetic, saleability, and product source identification concerns—those might be called functions but they are not the type of inventive functions that are eligible for utility patent protection.
But the courts have yet to make explicit the precise role, if any, of the relevant consumer’s perspective in this analysis, which would seem to be a legitimate inquiry in the trade dress context in a way it would not be in the utility patent context, for instance. Admittedly, the “ordinary observer” test used for infringement of design patents blurs this distinction somewhat, especially given that one appeals court has held that conflation of the trademark likelihood-of-confusion test and the design patent ordinary-observer test is harmless error.[xxx] But evidence of non-reputational consumer desires, such as a consumer survey or similar expert testimony, would appear to be rather unique to product configuration trade dress considerations and in closer cases might not always be answered or rendered unnecessary by the admissions or conduct of the alleged trade dress owner.
Certainly, many trade dress product configuration cases do turn on admissions or statements (such as ads) by the owner that indicate functionality or the failure of the owner to meaningfully rebut the persuasive articulation of functionality readily observable in the product itself. Additionally, parties aggressively enforcing trade dress have often also pursued or obtained another form of protection, such as a patent, and statements made in (or during the prosecution of) a patent on the same or similar subject matter can be relevant to trade dress functionality.[xxxi] The Supreme Court has gone so far as to explicitly note that invoking trademark rights as patent rights expire is suspicious enough to create “a strong implication” the party is seeking to improperly extend a patent monopoly and that summary disposition of anticompetitive strike suits is desirable.[xxxii] This means consumer surveys or the like should not become routinely necessary. Yet cases may arise where consumer perceptions of functionality (or usefulness) are not immediately apparent from the product configuration itself, or the plaintiff has not made damaging statements, making survey evidence informative in the absence of more straightforward grounds for assessing functionality. This seems like a potential additional (fifth) category of functionality evidence not spelled out in cases like Ezaki Glico.
Conclusion
Foodstuff product configuration trade dress disputes provide an excellent case study of how courts have sought to preserve consumer access to functional product features, as well as producer access to easy and economical manufacturing techniques. After all, the purpose of trademark law in general is supposed to be about helping consumers identify whether something originates from company A or company B, for instance, but it is not meant to give anyone a monopoly on that something itself. Unless product configurations are relatively easily avoided by competitors making basically the same products, assertions of trade dress protection in pure product configurations have often been rejected. While courts remain sensitive to potential confusion over a product’s source, valid product configuration trade dress rights, as a matter of branding, should include a prominent, non-functional feature related to reputation that does not significantly diminish consumer enjoyment or ease of manufacturability.[*]
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
[vii] See TrafFix Devices, Inc. v. Marketing Displays, Inc., 532 U.S. 23, 28-32 (2001); Wal-Mart Stores, Inc. v. Samara Brothers, Inc., 529 U.S. 205, 213-16 (2000); Qualitex Co. v. Jacobson Prods. Co., 514 U.S. 159, 164-65 (1995); Two Pesos, Inc. v. Taco Cabana, Inc., 505 U.S. 763, 771,775 (1992); Bonito Boats, Inc. v. Thunder Craft Boats, Inc., 489 U.S. 141 (1989); Inwood Labs., Inc. v. Ives Labs., Inc., 456 U.S. 844, 850 n.10 (1982); Sears, Roebuck & Co. v. Stiffel Co., 376 U.S. 225, 228-32 (1964); Compco Corp. v. Day-Brite Lighting, Inc., 376 U.S. 234, 238 (1964); see alsoScott Paper Co. v. Marcalus Mfg. Co., Inc., 326 U.S. 249, 255-57 (1945).
[viii] Sweet Street Desserts, Inc. v. Chudleigh’s Ltd., 69 F. Supp. 3d 530, 532-33 and 546-50 (E.D. Pa. 2014) aff’d 655 F. App’x 103 (3d Cir. 2016); see also 15 U.S.C. § 1064(3).
[ix] Sweet Street Desserts, Inc. v. Chudleigh’s Ltd., No. 5:12-cv-03363 (E.D. Pa. Jan. 15, 2015) aff’d 655 F. App’x 103.
[xi] Qualitex, 514 U.S. at 165 (quoting Inwood, 456 U.S. at 850, n.10).
[xii] Ezaki Glico, 986 F.3d at 257; accordPIM Brands Inc. v. Haribo of Am. Inc., No. 22-2821 (3d Cir. Sept. 7, 2023) (alleged trade dress of wedge shape and red/white/green color scheme made watermelon candy identifiable and reminiscent of a watermelon wedge and was therefore functional and unprotectable, with Principal Register registration ordered to be cancelled; “[f]unctionality is not a high bar” and “[e]ven if the design chosen both promotes a brand and also ‘makes a product work better,’ it is functional and unprotectable.” (citing Ezaki Glico, 986 F.3d at 258)); cf. Sulzer Mixpac AG v. A&N Trading Co., 988 F.3d 174, 182-84 (2d Cir. 2021) (color-coding to denote size of dental mixing tips improved the operation of the goods, which affects their quality, and therefore was functional and unprotectable as trade dress even though not essential).
[xiii] Ezaki Glico, 986 F.3d at 257 (quoting TrafFix, 532 U.S. at 32).
[xiv] Dippin’ Dots, Inc. v. Frosty Bites Dist., LLC, 369 F.3d 1197, 1203 (11th Cir. 2004); Groeneveld Transp. Efficiency, Inc. v. Lubecore Int’l, Inc., 730 F.3d 494, 506-09 (6th Cir. 2013); Schutte Bagclosures Inc. v. Kwik Lok Corp., 193 F. Supp. 3d 245, 261-62 (S.D.N.Y. 2016) aff’d 699 F. App’x 93, 94 (2d Cir. 2017).
[xvi] Ezaki Glico Kabushiki Kaisha v. Lotte Int’l Am. Corp., No. 2:15-cv-05477, 2019 WL 8405592 at *6 (D.N.J., 7/31/2019).
[xvii] See holder (61), which holds one end of stick-shaped pastries (40) while (only) the other end is immersed in a container (62) of liquid coating material (e.g., chocolate). U.S. Pat. No. 8,778,428, FIG. 5 and col. 5, lines 15-18 & 45-50.
[xviii] See TMEP §1209.01(b) (Oct. 2018).
[xix] Eskimo Pie Corp. v. Levous, 35 F.2d 120 (3d Cir. 1929).
[xx] Id. at 122; see also, e.g.,E.H. Tate Co. v. Jiffy Ents., Inc., 196 F. Supp. 286, 298 (E.D. Pa. 1961); James Heddon’s Sons v. Millsite Steel & Wire Works, 128 F.2d 6, 13 (6th Cir. 1942).
[xxi] Eskimo Pie Corp. v. Levous, 24 F.2d 599, 599-600 (D. N.J. 1928).
[xxiii] Id.; cf., Alice Corp. Pty. Ltd. v. CLS Bank Int’l, 573 U.S. 208, 223-24 (2014); Mayo Collab. Servs. v. Prometheus Labs, Inc., 566 U.S. 66, 72-73 (2012).
[xxiv] AmBrit, Inc. v. Kraft, Inc., 812 F.2d 1531, 1535-38 (11th Cir. 1986), cert. denied, 481 U.S. 1041 (1987), abrogated by Wal-Mart, 529 U.S. at 216, but see The Islay Co. v. Kraft, Inc., 619 F. Supp. 983, 990-92 (M.D. Fla. 1985).
[xxv] E.g., Spangler Candy Co. v. Tootsie Roll Inds., LLC, 372 F. Supp. 3d 588, 604 (N.D. Ohio 2019); Fiji Water Co., LLC v. Fiji Mineral Water USA, LLC, 741 F. Supp. 2d 1165, 1172-76 (C.D. Cal. 2010).
[xxvi] Dippin’ Dots, 369 F.3d at 1202-07; see also 15 U.S.C. §1125(a)(3). The court incorrectly stated unregistered product configuration trade dress can be inherently distinctive, a position abrogated by Wal-Mart.
[xxvii] Dippin’ Dots, Inc. v. Mosey., 476 F.3d 1337 (Fed. Cir. 2007).
[xxviii] Dippin’ Dots, 369 F.3d at 1205-06.
[xxix] See Keystone Mfg. Co., Inc. v. Jaccard Corp., No. 03-CV-648, 2007 WL 655758 (W.D.N.Y., Feb. 26, 2007).
[xxx] Unette Corp. v. Unit Pack Co., 785 F.2d 1026, 1029 (Fed. Cir. 1986); see also Converse, Inc. v. Int’l Trade Comm’n, 909 F.3d 1110, 1124 (Fed. Cir. 2018) (calling the standards “analogous”).
[xxxi] TrafFix, 532 U.S. at 29-32; Dippin’ Dots, 369 F.3d at 1205-06.
[xxxii] Singer Mfg. Co. v. June Mfg. Co., 163 U.S. 169, 181 (1896); Wal-Mart, 529 U.S. at 213-14; see alsoMorton Salt Co. v. G.S. Suppiger Co., 314 U.S. 488 (1942) (misuse of patent on machine to restrain unpatented salt tablet sales); Dastar Corp. v. Twentieth Century Fox Film Corp., 539 U.S. 23 (2003) (improper trademark law false designation of origin assertion after copyright expiration); EMI Catalogue P’ship v. Hill, Holliday, Connors, Cosmopulos, Inc., 228 F.3d 56, 63-54 (2d Cir. 2000) (“musical composition cannot be protected as its own trademark” because “[t]he creation and expression of an original work is protected by copyright law, and once an original work has been produced trademark law is not the proper means of protecting the rights in this originality”; declining to rule “that a product itself—in this case, the song—can serve as its own trademark”); Korzybski v. Underwood & Underwood, Inc., 36 F.2d 727, 728-29 (2d Cir. 1929) (election of protection doctrine bars copyright after obtaining patent: “An inventor who has applied for and obtained a patent cannot extend his monopoly by taking out a copyright . . . on what he has already diagrammatically disclosed”) accord Vacheron & Constantin-Le Coultre Watches, Inc. v. Benrus Watch Co., 260 F.2d 637, 642 (2d Cir. 1958) (“grant of a patent presupposed a dedication to the public of the disclosure, except so far as the statute specifically reserved it to the patentee”).
Under U.S. federal trademark law, a trademark registration can be refused or trademark infringement found if there is a likelihood of confusion. The “likelihood of confusion” standard covers more than identical uses, intentional copying, counterfeiting, and knock-offs. It is ultimately a question of determining what ordinary consumers understand and what would confuse them. Trademarks (and service marks) are intended to avoid consumer confusion about the source of commercially available goods and services. So these issues go to heart of trademark law.
Likelihood of confusion is a multi-factor analysis. There are a number of different facts that are taken into account in order to draw a legal conclusion about the likelihood an appreciable number of consumers would be confused. Each individual factor can point toward or away from confusion, or be neutral. Different factors can carry different weight in the overall analysis depending on the circumstances.
Keep in mind, however, that the likelihood of confusion analysis is about whether an appreciablenumber of ordinary consumers is likely to be confused. That a few undiscerning or careless prospective purchasers might occasionally be confused is not enough. There is generally no obligation under trademark laws to protect negligent, indifferent, inattentive, or careless purchasers from confusion or to make the market foolproof. The owner of a trademark is not entitled to a guarantee against confusion in the minds of careless and indifferent buyers. Even evidence of actual confusion among a few customers may be de minimis and not conclusive of likelihood of confusion.
A reliable consumer opinion survey is highly informative about likelihood of confusion. Actually, it is usually the best kind of evidence. But surveys are complicated and costly. The practical difficulty is to make a judgment about the likelihood of confusion without having survey results available.
A useful exercise is to try to envision a hypothetical consumer survey. This can help you be more objective and avoid looking at likelihood of confusion in too self-serving a way. Splitting hairs about insignificant differences is a common mistake. Thinking that established rights extend to any and all goods and services (that is, thinking that similar marks can never coexist) is also a common mistake. But turning to the idea of a hypothetical survey of ordinary consumers might help avoid those biases. Because, in the end, the likelihood of confusion question is about ordinary consumers’ perspectives not your own.
The specific list of factors considered is phrased in different ways by various courts and the U.S. Patent & Trademark Office (USPTO)—as discussed further below. But under the any formulation of likelihood of confusion factors, the overall analysis is similar. The marks do not have to be identical. Similarly, the respective goods/services do not have to be identical. It is sufficient that they are related in such a manner that an appreciable number of ordinary purchasers are likely to assume—mistakenly—that they originate from a common source.
Registrations at the USPTO
In the USPTO, six so-called DuPontfactors are used for the likelihood of confusion analysis. These DuPont factors can be used to refuse registration because there is a prior conflicting registration. They can also be used in deciding oppositions to applications and attempts to cancel an existing registration based on prior use of a mark. Two DuPont factors are always considered:
similarity or dissimilarity of the marks in their entireties as to appearance, sound, connotation, and commercial impression
relatedness of the goods or services as described in the application and prior application(s)/registration(s)
Four additional DuPont factors might also be considered, though there may not be any evidence available to allow consideration of these other factors:
similarity or dissimilarity of established, likely-to-continue trade channels (that is, actual sales methods used)
conditions under which and buyers to whom sales are made (for instance, “impulse” vs. careful, sophisticated purchasing)
number and nature of similar marks in use on similar goods or services
existence of a valid consent agreement between the applicant and the owner of the previously registered mark
The six factors listed above are actually a condensed list of the ones that are most commonly relevant in the examination of new applications. The DuPontcase actually set forth a total of thirteen factors. Though the other factors omitted from the condensed list above rarely come up except for certain contentious cancellation or opposition proceedings where an opposing party is involved, and even then may not be as significant as other factors.
The weight given to any of these individual factors can vary. There is no precise mathematical formula for how they are applied to reach a conclusion. Though the comparison always involves the specific mark and the specific goods or services identified in the application or registration in question. Actual uses of the mark in the marketplace that are not identified in the application or registration at hand are generally irrelevant—the USPTO only decides what can or cannot be registered. Questions about infringement are dealt with by courts instead.
The USPTO provides some useful hypothetical examples of likelihood of confusion comparisons.
Disputes in Court
Courts decide infringement allegations as well as issues about the validity of trademark rights. But there are slightly different formulations of the likelihood of confusion factors applied in courts from different parts of the country. So the applicable factors will depend on which “circuit” handles a given case.
For instance, in the 8th Circuit—whose jurisdiction covers the states of Minnesota, Iowa, Missouri, Arkansas, Nebraska, South Dakota, and North Dakota—six so-called SquirtCo factors are used to assess likelihood of confusion:
the strength of the owner’s mark
the similarity between the owner’s mark and the alleged infringer’s mark, based on an examination of the marks as a whole
competitive proximity (the degree to which the products compete with each other, though infringement may be found in the absence of direct competition)
the alleged infringer’s intent to “pass off” its goods as those of the trademark owner raises an inference of likelihood of confusion, but intent is not an element of a claim for trademark infringement
incidents of actual confusion (if any; not required to establish likelihood of confusion; requires more than isolated incidents of inattentiveness; its presence is also not conclusive of likelihood of confusion)
the type of product, its costs and conditions of purchase
The weight given to any of the factors for likelihood of confusion can vary. And there is no mathematical formula for applying them. Depending on the evidence available, some factors may be more important than others.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.
Recent Federal Circuit cases highlight a confused standard applied to discretionary enhanced damages determinations in patent infringement cases. As will be shown, the Federal Circuit has elevated the statement of mind requirement for enhanced patent damages contrary to Supreme Court precedent.
In Halo, the Supreme Court discussed how conventionally reckless conduct at the time of the conduct in question supports punitive damages for patent infringement under 35 U.S.C. § 284. Halo Elecs., Inc. v. Pulse Elecs., Inc., 979 U.S. ___, ___, 136 S. Ct. 1923, 1932-35 (2016) (“The principal problem with Seagate[] . . . is that it requires a finding of objective recklessness in every case before district courts may award enhanced damages. Such a threshold requirement excludes from discretionary punishment many of the most culpable offenders”). After-the-fact rationalizations drummed up during litigation were at odds with the conventional understanding of recklessness, which requires analysis of the accused’s state of mind at the time of the actions in question. Id. at 1930,1933. The Court clarified that “a person is reckless if he acts ‘knowing or having reason to know of facts which would lead a reasonable man to realize’ his actions are unreasonably risky.” Id. at 1933 (emphasis in original); cf. Sherry F. Kolb, “Why Can’t Jurors Distinguish ‘Knowing’ From ‘Reckless’ Misconduct?”Verdict (Jan. 11, 2012) (discussing subjective states of mind in the criminal law context, with helpful illustrative examples). “Section 284 allows district courts to punish the full range of culpable behavior[] . . . in a manner free from the inelastic constraints of the Seagate test.” Halo, 136 S. Ct. at 1933-34. In a way, Halo‘s ruling about conventional recklessness standards fits with other Supreme Court cases (like eBay v. MercExchange) striking down special rules and holding that patent matters are generally subject to the same standards that apply in other types of civil tort cases.
Since Halo, the Federal Circuit has been eager to restrict the Supreme Court’s holding to only a first step in a multipart analysis under § 284 despite the Supreme Court’s expansive discussion about “punish[ing]” the “full range of culpable behavior.” The Federal Circuit has, to some extent, lost the forest for the trees by focusing rather myopically on one sentence in Halo: “The subjective willfulness of a patent infringer, intentional or knowing, may warrant enhanced damages, without regard to whether his infringement was objectively reckless.” Id. at 1933. In doing so, Halo‘s ultimate holding that enhanced damages are available for conventional recklessness is lost.
The Federal Circuit currently maintains a two-step process for analysis of enhanced damages under 284. “[Halo] leaves in place our prior precedent that there is a right to a jury trial on the willfulness question. *** Whether the conduct is sufficiently egregious as to warrant enhancement and the amount of the enhancement that is appropriate are committed to the sound discretion of the district court.” WBIP, LLC v. Kohler Co., 829 F.3d 1317, 1341-42 (Fed. Cir. 2016). So, first, the finder-of-fact determines “willfulness” and, second, the court has discretion to impose enhanced damages, if any.
For the first step, the Federal Circuit has said that willfulness can be found if the accused infringer “acted despite a risk of infringement that was ‘ ‘either known or so obvious that it should have been known . . . .’ ‘ ” WesternGeco LLC v. ION Geophysical Corp., 837 F.3d 1358, 1362 (Fed. Cir. 2016) (emphasis added), reinstated 913 F.3d 1067, 1075 (Fed. Cir. 2019); accord Arctic Cat, Inc. v. Bombardier Recreational Prods. Inc., 876 F. 3d 1350, 1371 (Fed. Cir. 2017) (willfulness supported if accused infringer “actually knew or should have known that its actions constituted an unjustifiably high risk of infringement of a valid and enforceable patent.”). Halo used the phrase “having reason to know” while the Federal Circuit has, without explanation, instead used the phrase “should have known”.
The second step is a moral judgment that falls to the discretion of the district court. But enhanced damages do not automatically follow from a finding of willfulness. Halo, 136 S. Ct. at 1933 (“Yet none of this is to say that enhanced damages must follow a finding of egregious misconduct.”); see also Presidio Components, Inc. v. Am. Technical Ceramics Corp., 875 F.3d 1369, 1382 (Fed. Cir. 2017) (“an award of enhanced damages does not necessarily flow from a willfulness finding.”).
In Eko, the Federal Circuit ruled on jury instructions for willfulness. Eko Brands, LLC v. Adrian Rivera Maynez Enters., Inc., 946 F.3d 1367, 1377-79 (Fed. Cir. 2020). The most controversial passage in that opinion was the assertion that “[u]nder Halo, the concept of ‘willfulness’ requires a jury to find no more than deliberate or intentional infringement.” Id. at 1378 (emphasis added). Merely implicit in the court’s opinion is that the issue was a defendant challenging a jury instruction (based upon the Federal Circuit Bar Association’s (“FCBA’s”) National Patent Jury Instructions) upon which the jury found willful infringement. In other words, while the jury instruction may have omitted reckless conduct that Halo had found sufficient to support willfulness and enhanced damages, that point was moot and not at issue in the Eko appeal because the jury had found that even a heightened state of mind (beyond recklessness) was present. But the court’s reference to “no more than” deliberate or intentional conduct is the confusing part, because it is odd, to say the least, to describe a heightened intent standard with a phrase like “no more than” that normally connotes a low threshold.
Then the Federal Circuit offered a rationalization of Eko in SRI International. SRI Int’l, Inc. v. Cisco Sys., Inc., No. 20-1685, Slip. Op. at *9-10 (Fed. Cir., Sept. 28, 2021). There, a district court had noted that “the [Federal Circuit] is not entirely consistent in its use of adjectives to describe what is required for willfulness.” SRI Int’l, Inc. v. Cisco Sys., Inc. (SRI III), No. 13-1534, 2020 WL 1285915, at *1 n.1 (D. Del., Mar. 18, 2020). So the Federal Circuit responded: “To eliminate the confusion created by our reference to the language ‘wanton, malicious, and bad-faith’ in Halo, we clarify that it was not our intent to create a heightened requirement for willful infringement. Indeed, that sentence from Halo refers to ‘conduct warranting enhanced damages,’ not conduct warranting a finding of willfulness.” SRI Int’l, No. 20-1685, Slip. Op. at *9-10 (Fed. Cir., Sept. 28, 2021). This actually adds to rather than eliminates confusion, by emphasizing rather minor procedural points as a kind of shell game but doubling down on the aspect that runs contrary to recent Supreme Court precedent. The partial and selective quotation from Halo omits a number of grounds the Supreme Court held can support an award of enhanced damages. The relevant sentence in Halo reads in full: “The sort of conduct warranting enhanced damages has been variously described in our cases as willful, wanton, malicious, bad-faith, deliberate, consciously wrongful, flagrant, or — indeed — characteristic of a pirate.” Halo, 136 S. Ct. at 1932. Notice how the Federal Circuit’s quote drops the word “willful” and others? And recall from above how Halo was primarily about enhanced damages awards encompassing conventional recklessness?
The Disputed and Confusing Continuum of States of Mind for Willfulness and Enhanced Damages in Patent Cases, Before and After Halo
The visualization above is meant to show that there is a continuum of states of mind for “willfulness”, though there is a long line of cases from different areas of law that show that there is no definitive definition of how to describe “willful” intent in civil matters. Indeed, Justice Breyer’s concurrence in Halo noted that “‘[w]illfu[l]’ is a ‘word of many meanings whose construction is often dependent on the context in which it appears.'” Halo, 136 S. Ct. at 1936 (Breyer, J., concurring) (also contrasting behavior that is not “wanton” or “reckless”) (quoting Safeco Ins. Co. of Am. v. Burr,551 U.S. 47, 57 (2007), a case relied upon by the majority). Though it is indisputably clear that Halo found that conventional recklessness qualifies as willfulness for enhanced patent damages.
A typical description of recklessness is conscious and willful indifference to the risk imposed on the unlucky victim; not that the defendant intended to harm the victim, but that he knowingly imposed a risk on the victim, which could have been eliminated with minimum effort. See Anthony J. Sebok, “Purpose, Belief, and Recklessness: Pruning the ‘Restatement’ (Third)’s Definition of Intent,” 54 Vanderbilt Law Review 1165, 1177 (2001) (discussing punitive damages in product liability cases). Yet there is potential circularity in any continuum that would partly define one degree of “willfulness” in the patent context as “willful indifference”.
Despite argument over the proper descriptors of degrees of willful intent, the Supreme Court has said that these distinctions may be troublesome but are nonetheless necessary and that “the difference between one end of the spectrum—negligence—and the other—intent—is abundantly clear.” Daniels v. Williams, 474 U.S. 327, 334-35 (1986) (citing LeRoy Fibre Co. v. Chicago, M. & St. P. R. Co., 232 U.S. 340, 354 (1914) (Holmes, J., partially concurring) and O. Holmes, The Common Law 3 (1923)). But in Eko the Federal Circuit discusses only the opposite end of the spectrum from negligence and not the troublesome “middle” degrees of willful intent—namely the lowest degree of willful intent set forth in Halo: recklessness. In other areas of law, courts distinguish a “deliberate” state of mind as from a “reckless” one, with “deliberate” representing a higher degree of intent than “recklessness”. E.g., Express Scripts, Inc. v. Bracket Holdings Corp., 248 A.3d 824, 825 (Del. 2021) (“A deliberate state of mind is a different kettle of fish than a reckless one.”). It is problematic, to say the least, for the Federal Circuit to sidestep entirely these troublesome but necessary distinctions in degree by using terminology like “deliberate” and “intentional” that typically connotes a higher degree of intent than the recklessness standard set forth in Halo.
Further complicating matters is that the Federal Circuit has taken a contradictory position about what “should have known” means in patent and trademark cases. Sometimes the Federal Circuit says “should have known” means negligence while at other times appears to say it means recklessness. For instance, more than a decade ago it clarified the requirements to establish when fraud on the USPTO bars trademark registration. The Federal Circuit rejected the TTAB’s “should have known” fraud standard because it — supposedly — correlates to mere negligence. In re Bose Corp., 580 F.3d 1240, 1244 (Fed. Cir. 2009) (“[B]y equating ‘should have known’ with a subjective intent,” the TTAB “erroneously lowered the fraud standard to a simple negligence standard.”). The Federal Circuit has also interpreted “should have known” as equating to negligence in patent cases involving active inducement of infringement. And yet, in WesternGeco and Arctic Cat the Federal Circuit held that “should have known” is an appropriate standard for willfulness in patent cases under Halo. And Halo made clear that “a person is reckless if he acts ‘knowing or having reason to know of facts which would lead a reasonable man to realize’ his actions are unreasonably risky” and that such recklessness is sufficient to award enhanced damages. Halo, 136 S. Ct. at 1933; see alsoMotiva Patents, LLC v. Sony Corp., 408 F. Supp. 3d 819, 837 (E.D. Tex. 2019) (“Halo holds that recklessness alone is enough to show willful infringement.”).
Halo abrogated at least the “inelastic” part of Seagate that set the threshold for willfulness and enhanced damages too high because if failed to allow enhancement for conventional (subjective) reckless intent at the time of the conduct at issue. Now (since Eko and SRI), the Federal Circuit has seemingly done an end-run around Halo by requiring an elevated level of intent beyond recklessness in order to support discretionary “enhanced damages” following a finding of willfulness. An issue here is that Halo said, “Consistent with nearly two centuries of enhanced damages under patent law, however, such punishment should generally be reserved for egregious cases typified by willful misconduct.” Halo, 136 S. Ct. at 1933-34. But recent Federal Circuit cases make no reference to that nearly two century history and instead utilize rather tendentious, selective, and partial quotations from Halo suggesting that a heightened state of mind beyond conventional recklessness is required for enhancement following a willfulness determination (contrary to the holding in Halo).
In the past, the Federal Circuit said that willfulness and discretionary enhancement analyses were basically the same. E.g., SRI Int’l, Inc. v. Advanced Tech. Labs., Inc., 127 F.3d 1462, 1469 (Fed. Cir. 1997) (“The principal considerations in enhancement of damages are the same as those of the willfulness determination, but in greater nuance as may affect the degree of enhancement.”). The Read factors commonly used for these analyses were about the totality of the circumstances and did not draw any categorical distinctions between degrees of intent within the category of willfulness (e.g., between recklessness and knowing/deliberate states of mind). Now, the Federal Circuit seems to be heading in another direction with (purportedly) a different standard for discretionary enhancement than for willfulness determinations. See Ryan Davis, “Fed. Circ. Outlines Willfulness, Enhanced Damages Standards,”Law360 (Oct. 7, 2021).
So today patentees face a situation in which the Federal Circuit seems to have merely pushed the abrogated initially high (“objective recklessness”) threshold of Seagate to the back end of the discretionary enhanced damages analysis, with what looks unmistakably like a heightened subjective intent requirement—higher than, and contrary to, the conventional recklessness standard set forth in Halo. Though another way to look at this is to say that the Federal Circuit has actually heightened the threshold “willfulness” standard too, even though they deny doing so, because a “deliberate or intentional” requirement has long been considered a heightened level of intent compared to conventional recklessness. Either way, this seems to shield merely reckless conduct from punishment, contrary to Halo, and is an untenable position for the Federal Circuit that calls for either an en banc reversal or further action by the Supreme Court.
P.S. — I should have a magazine article forthcoming in mid-2022 dealing with willfulness/enhanced damages. It will discuss the way district courts have frequently overlooked (or even ruled contrary to) 35 U.S.C. § 298 when dealing with issues involving the minimum requirements for willfulness and the way some district court cases (not yet reached in any precedential Federal Circuit decision) seem to resurrect something that looks like the old, abrogated “duty of due care” standard that corresponded to mere negligence.
Austen Zuege is an attorney at law and registered U.S. patent attorney in Minneapolis whose practice encompasses patents, trademarks, copyrights, domain name cybersquatting, IP agreements and licensing, freedom-to-operate studies, client counseling, and IP litigation. If you have patent, trademark, or other IP issues, he can help.