The phrase “prior art” is used extensively in relation to patents and patenting. But what is prior art? What does this term refer to? The following article will explain how this term is used in patent law.
Basic Overview
Prior art refers to what was already known that is relevant to patentability. More particularly, it is qualifying existing knowledge that is relevant to questions of novelty and nonobviousness (or inventive step), which are two requirements for patentability, for an invention recited in a given claim of a patent or patent application.
Of course, there are some further nuances here about what exactly is considered relevant to patentability and what is not, and what legally qualifies as prior art under applicable law. Many of those nuances are explained further below.
Prior Art is Old Knowledge
First of all, prior art has to be old enough. It always has to be something that was already known or came before before a particular date associated with a given patent or patent application. So the “prior” part of the term “prior art” means something was known sufficiently earlier or before what given inventor(s) are claiming is their patentable invention. This is about dividing technical knowledge into older stuff that might call the patentability of an invention into question and later stuff that might infringe claim(s) of a patent to that invention.
For any given patent or patent application, there is a critical date that establishes what is old enough to be prior art. Something before the critical date is prior art and anything after is not. The point in time that constitutes a critical date will be established by the patent laws of a particular jurisdiction. It can vary based on whether a jurisdiction follows a first-to-file patent system or a first-to-invent patent system, for example. It can also vary on a claim-by-claim basis—there may be different priority dates for different claims, which means some things may be prior art against certain claims but not others.
Prior Art is Knowledge of Useful Arts
The “art” part of the term “prior art” refers to knowledge about the useful arts. The “useful arts” is basically an old-fashioned term that refers to technical knowledge pertaining to what today is more commonly called science and engineering. Just as there are different fields of science and engineering, there are different types of arts. So this term is not limited to any particular area or kind of technical knowledge. But it does not refer to paintings, sculptures, or similar artworks that might appear in a museum.
The term “prior art” can refer to the collective body of relevant prior technical knowledge. That means it is proper to say that something falls within the prior art, as in being a part of that body of pre-existing knowledge. It is common to refer to a “prior art reference”, “prior art product”, or the like in reference to a particular instance of something that qualifies (or allegedly qualifies) as prior art.
Prior Art is Essentially Public Knowledge
In general, prior art refers to information that was sufficiently accessible to the public. This might have been in the form of commercially-available products or services, or in the form of articles, books, videos, etc. Importantly, something that was “secret” and not available to the public usually will not qualify as prior art. For instance, an unpublished draft of a book or article will not qualify as prior art. But there are some exceptions that may allow certain secret or confidential activities to qualify as prior art, mainly relating to confidential on-sale activities.
A crucial exception (at least in the USA) is that any sale or offer for sale can potentially qualify as prior art. The U.S. on-sale bar still applies to prior confidential, private, or otherwise secret commercial sales or offers for sale. In other words, a confidentially or non-disclosure (NDA) agreement will not remove something that was on sale from the realm of prior art. Such confidential sales still involve a third-party (who is part of the public) gaining access to an invention. Also, inventor(s)’ own prior activities can potentially be used as prior art against the inventor(s)’ later patent application or patent, unless the inventor(s)’ application was filed in the statutory grace period.
Laws Vary By Jurisdiction
Prior art is also something defined by the patent laws of a given jurisdiction. This means that definitions of what is and is not considered prior art can and do vary between different countries. There is no universal harmonization of patent laws in this respect. So it is possible something might qualify as prior art in one country but not in another.
In the USA, what constitutes prior art is set out in § 102 of the patent laws (35 U.S.C. § 102). This portion of the current patents laws is written in a very confusing manner. But it establishes that prior art can include a patent, a published patent application, a printed publication (which can also include patents and published patent applications), products or processes that were in public use or on sale, as well as things that were otherwise available to the public before the effective filing date of the claimed invention. U.S. patent law also contain some exceptions that can disqualify certain references from being used as prior art.
In other countries, however, the patent laws may differ significantly. For instance, some countries have no on-sale bar, only a public use bar to patenting. This means that secret or confidential sales may not qualify as prior art, even if those prior secret sales involved the identical invention. And few other countries have a filing grace period like the U.S. Some jurisdictions may also have limits on the use of prior art, such as making an applicant’s prior patent applications available as prior art only for novelty determinations but not inventive step/obviousness determinations. It is important to consider laws of each relevant jurisdiction separately, because differences in laws can mean that what qualifies as prior art differs between jurisdictions.
Laws Change Over Time
What qualifies as prior art can also change over time in a given jurisdiction as laws are modified or interpreted by courts.
U.S. patent laws have changed over time, including modifications to the definitions of what does and does not qualify as prior art. Significantly, the America Invents Act (AIA) had provisions that went into effect March 16, 2013 that eliminated certain first-to-invent provisions and altered other aspects of what qualifies as prior art. For example, the AIA eliminated certain geographic restrictions on what qualifies as prior art—no longer requiring that certain things happen in this country (i.e., in the USA) to be prior art. Patents and patent applications with pre-AIA effective filing dates are therefore subject to different definitions of what qualifies as prior art than post-AIA ones. Laws in other countries have also changed over time.
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.
These downloadable materials from a past live presentation address basic marking requirements and best practices for patent marking, as well as requirements for virtual marking, alternative marking on a label or package, ways the sufficiency of marking can be challenged, and false marking. These materials cover the ins and outs of patent marking in a format packed with real-world examples.
Marking is simple enough in concept but there are a surprising number of nuances and practical challenges for implementation. Also, the America Invents Act (AIA) reshaped numerous aspects of marking that continue to reverberate. For instance, virtual marking was introduced with the AIA and there is now a growing body of court decisions clarifying what kinds of virtual marking practices are sufficient and what kinds are not. These practical aspects of marking are addressed in these program materials.
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.
Patents have a maximum term and cannot be renewed. This is part of the quid pro quo underlying modern patent law. The patentee gets exclusive rights for a limited time but then the technology disclosed in expired patents can be freely used by the public (in at least the jurisdiction that issued the patent). Knowing how to calculate patent term is therefore important in order to determine when a given patent has expired. But, for better or worse, the term of any given patent can vary. There is no single fixed term for all U.S. patents. And the applicable term is not always apparent on the face of a given patent. So how is patent term calculated for U.S. patents?
USPTO Patent Term Calculator
One of the simplest and most practical ways to determine the term of a given U.S. patent is to utilize a patent term calculator provided by the U.S. Patent & Trademark Office (USPTO). Using this downloadable spreadsheet requires inputting certain information about a given patent. Only some of the necessary information appears printed on a granted patent. Other information must be researched in USPTO records, mainly through Patent Center.
The advantage of the USPTO’s patent term calculator is that it can be used by anyone, even people who do not understand the applicable patent laws. However, it still requires ascertaining the correct information to enter in the spreadsheet. That requires knowing where to find such information. The patent term calculator also requires a level of confidence that the correct information is being entered. That is, it still requires knowing some of the terminology so that correct, relevant information is entered.
Read on for more information about the sorts of information relevant to proper patent term calculations.
Relevant Factors
What follows is a more detailed explanation of factors that determine the enforceable term of a given patent. These factors include factors that influence how to calculate a given patent’s term, as well as things that might cut short the enforceable term of a given patent. In any given instance, consulting with a knowledgeable patent attorney is recommend to determine the correct term of any given U.S. patent.
Type of Patent
Paten term first of all depends on the type of patent involved.
U.S. utility and plant patents have a basic term of 20 years from the relevant filing date (35 U.S.C. § 154)—there being some nuance about which filing date is used here.
Timeline Showing Basic Patent Term for U.S. Utility and Plant Patents (Including PCT National Phase Entries)
A priority claim to a foreign patent application (stemming from the Paris Convention or a PCT application that did not designate the USA) or to a prior U.S. provisional patent application does not count against the term (35 U.S.C. § 154(a)(3)). This means a foreign priority or prior provisional filing can effectively extend patent term.
Timeline Showing Basic Patent Term for U.S. Utility and Plant Patents Based on a Prior U.S. Provisional or Foreign Priority Application
For regular PCT national phase entries to the USA, the PCT international filing date is used for term calculation (not the date of later U.S. national phase entry). That is, a PCT international application designating the United States is treated as a U.S. application (see 35 U.S.C. §§ 372 and 375), with the national phase being just a different phase of the same application. So an ordinary national phase entry into the United States does not, by itself, involve a “priority” claim–although there may additionally be a priority claim involved.
The so-called domestic benefit of a prior U.S. non-provisional application (that is, for a continuation, continuation-in-part, or divisional application under 35 U.S.C. §§ 120, 121, 365(c), or 386(c), including PCT “bypass” applications) does count against patent term, so the term calculation should be based on the earliest such prior filing date. In other words, continuing applications that have priority/domestic benefit of a prior U.S. non-provisional application will have a reduced patent term. The related U.S. application data field (INID code 63) on the face of a patent, if present, can indicate an earlier filing date that may impact term.
Timeline Showing Basic Patent Term for Continuing U.S. Utility and Plant Patents Based on a Prior Domestic U.S. Application (Including PCT “Bypass” Applications)
Example of INID code 63 “Related U.S. Application Data” field on front page of U.S. Pat. No. 11,102,682, showing earliest filing date for patent term calculation of a continuing application
In contrast, U.S. design patents currently have a fixed basic term of 15-years from the date of grant (35 U.S.C. § 173). The filing date issues referenced above do not impact design patent term. This means that continuing design patents can potentially have later expiration dates, unlike with utility and plant patents.
Timeline Showing Basic Patent Term for U.S. Design Patents
Reissue patents are possible “for the unexpired part of the term of the original patent.” (35 U.S.C. § 251). This means that a reissue patent’s term is no longer than the term of the original patent, as subject to any extension or adjustment. It is possible that a reissue patent’s term could be shorter than that of the original patent (see discussion of terminal disclaimers below). But reissue does not lengthen patent term.
Filing Date and Changes in the Law
The laws around patent term have changed over time. Some patents applied for or granted prior to those changes in the law may be subject to a different term.
U.S. utility and plant patents applications filed before June 8, 1995 can have a term of 17 years from the date or grant rather than from the earliest applicable filing date. Any patent that was in force on June 8, 1995 will have a term that is the greater of the 20-year term as discussed above or 17 years from grant (35 U.S.C. § 154(c)).
For U.S. design patents, those issued from design applications filed before May 13, 2015 have a 14-year term from the date of grant (rather than 15-years from grant).
Of course, there may be future changes in the law that affect patent term calculations. And courts may issue decisions that affect the interpretation of laws that impact patent term calculations.
Patent Term Adjustment
Certain delays in examination can lead to an adjustment of patent term for a given original patent (but not for a reissue). This is called patent term adjustment (PTA) under 35 U.S.C. § 154(b). Normally, this PTA is calculated as the number of days beyond the basic 20-year term that the patent can remain in force. The PTA period normally appears on the face of each granted patent—typically in a “Notice” field denoted with an asterisk (*). The USPTO’s Patent Center portal also has a menu tab showing detailed PTA calculations for a given patent. However, it is possible for a patentee to challenge the USPTO’s PTA calculation in some circumstances, meaning the PTA period might be corrected later. PTA does not apply to design patents.
Example of PTA notice on front page of U.S. Pat. No. 10,000,000, showing 430 days of additional patent term
Patent Term Extension
Patentees can potentially obtain patent term extension (PTE) under 35 U.S.C. § 156 based upon premarket regulatory review of certain human drugs, food or color additives, medical devices, animal drugs, and veterinary biological products. This restores some term lost while awaiting premarket government approval from a regulatory agency. An application for PTE must be submitted within sixty (60) days of when permission for commercial marketing or use occurred. Patentees have to affirmatively apply for PTE, which is not automatically granted. Also, PTE is only possible for patents on certain types of subject matter; it does not apply to design or plant patents. § 156 PTE is not indicated on granted patents and must be researched in USPTO records, mainly through Patent Center.
Disclaimers
A given patent may be subject to a disclaimer (35 U.S.C. § 253). The two types of disclaimers are a terminal disclaimer or a statutory disclaimer.
In a terminal disclaimer, the patentee disclaims or dedicates to the public a portion of the term of a given patent. That is, the term of the patent is shortened from what it might otherwise be. Terminal disclaimers are frequently used to overcome double patenting, by disclaiming the period of patent term (if any) that would extend beyond that of one or more other patents. They are also used when design patent applications are revived after abandonment, disclaiming a period of patent term equal to the period of abandonment. Terminal disclaimers do not affect § 156 PTE, however.
Example of terminal disclaimer notice on front page of U.S. Pat. No. 11,102,682
Excerpt from example terminal disclaimer filed against U.S. Pat. No. 11,102,682, disclaiming term beyond that of U.S. Pat. No. 10,667,181
The USPTO has sometimes, but not always, printed an indication that a given patent is subject to a terminal disclaimer on the front page of the patent. Terminal disclaimers can also arise after a patent has been granted. In any event, the duration (and possibly also the existence) of a terminal disclaimer must be researched in the prosecution history of the relevant patent in USPTO records. This can generally be done using the online Patent Center portal and viewing the “Documents & Transactions”. Although the calculation of the disclaimed period may require additional research and analysis. For instance, it may be necessary to calculate the term of one or more other patents or the period of applicant delay for a design patent.
For statutory disclaimers, one or more claims of a patent are effectively surrendered. This means that some claims may no longer be in force, even though other claims might.
Lapse or Expiration for Non-Payment of Maintenance Fees
In order to keep a given U.S. utility patent in force, periodic maintenance fees are required (35 U.S.C. § 41(b)). These are due by four, eight, and twelve years from the grant of the patent. However, there are no maintenance fees required for U.S. design patents or plant patents (37 C.F.R. § 1.362(b)).
If a maintenance fee is not paid on time, then the patent will lapse or expire. This means that a given utility patent might no longer be in force even though it has not yet reached its maximum possible term.
What makes lapses/expirations complicated is that the patentee may be able to reinstate (that is, revive) the patent if a maintenance fee payment deadline was missed unintentionally. This may give rise to intervening rights (35 U.S.C. § 41(c)(2)). So, significantly, the expiration or lapse of the U.S. patent due to a missed maintenance fee may not mean the final and absolute end of rights in that patent if late payment is accepted.
Terminology describing this lapses/expiration for non-payment of maintenance fees hasvaried. The USPTO currently tends to use “expiration” but “lapse” is a better term because it differentiates situations where revival is possible from those in which a patent’s term has expired permanently because it has reached its maximum limit.
Invalidation and Cancellation
Patents can be invalidated by courts or cancelled by the USPTO, usually as the result of a challenge by another entity. This can affect all or merely some claims of a patent. Such an adverse ruling (after exhaustion of all rights of appeal) can end or limit rights in the patent short of its maximum possible term. It is necessary to research the existence and status of such an adverse ruling, if any.
Withdrawn Patents
Lastly, some patent numbers have been withdrawn by the USPTO. These were essentially never really patents in the first place, for various reasons, and thus have no term. Although, to complicate matters, the USPTO has also reinstated some previously withdrawn patents.
Laws Vary by Jurisdiction
The discussion above pertains only to U.S. patents. In other countries, laws may differ regarding the calculation of patent term, the availability of supplementary protection certificates, and so on.
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.
Preparing new patent applications can be complicated. Patent applications in the U.S. and most other countries undergo pre-grant examination. So a patent application must be sufficient to establish patentability to the satisfaction of a patent examiner. And if the goal is to create enforceable exclusive legal rights in an invention, and it usually is, then there are many legal considerations that impact coverage and validity. In sum, while there are challenges to obtaining any patent at all, not all granted patents are equal.
What follows is a discussion of some of the most common mistakes when drafting a utility patent application. These are the sorts of mistakes frequently made by inventors preparing and filing an application themselves (pro se) without the aid of a patent attorney. These issues can also arise when applications prepared in another jurisdiction enters the USA and there are differences in the law and practices in the two jurisdictions.
A discussion of common mistakes in design patent applications is available elsewhere.
Focusing on the Old Rather than the New
One common mistake, especially with applications self-prepared by inventors, is to focus on the prior art and what is old and already known rather than on the new invention. Put another way, the mistake is to devote excessive effort to describing what the invention is not rather than what it is. While it is permitted to discuss the background of the invention, and sometimes this is helpful to highlight what is new and different about the invention, this provides little benefit when it takes up too large a proportion of an application.
As an example, criticizing existing products for being “too slow” and stating that it is desired to have an improved product that works faster might be helpful for context. But unless the application further explains how better results and faster speeds are achieved, such a discussion of the background context has fairly limited value. Also, if the discussion of what was known is far more detailed than the discussion of what is supposedly new, this can have the undesired effect of suggesting that the inventors have yet to adequately develop the invention to a point of being patentable.
Omitting How It Works, or “Black Box” Gaps
A big mistake is failing to describe what the new invention is and how it works in sufficient detail. Often this means describing what is new too superficially so that it is no more than a plan for future invention or a mere statement of a problem to be solved or a desired result. Modern patent laws a premised on a quid pro quo: in exchange for disclosing how to make and use an invention, exclusive rights are granted for a limited time. But you cannot get exclusive patent rights by withholding the “secret” of how to make and use the invention.
Occasionally, this problem arises by placing important aspects of the invention in a “black box”. If key steps, ingredients, or structures are withheld from the disclosure contained in a patent application, then the patentability requirement of enablement (35 U.S.C. § 112(a)) is not met.
Stated more generally, it is necessary to provide a disclosure that enables someone of ordinary skill in the art to make and use the full scope of the invention as defined by the claims. The more one claims, the more one must enable. So a more limited disclosure might only support more limited claims. Sometimes this is a genus/species issue — a question of the sufficiency of disclosure of particular species to claim an entire genus. It is therefore necessary to have claims that are commensurate with the scope of the disclosure and not overbroad, or, from another perspective, to have a disclosure that is robust enough to support the desired claim scope.
One helpful thing (good) patent attorneys do is that they explain how inventions work in a understandable way. The technology may still be complicated. So the explanatory disclosure might not be entirely “easy” to read and understand. But inventors are sometimes able to devise working inventions without being able to translate that technology into words and drawings of the sort required for patent applications. It may be because they take some things for granted, or sometimes they might not even fully grasp what is different about their new invention from what was known before.
Lastly, there is still a requirement that the “best mode” of practicing an invention be disclosed. Applicants and inventors cannot disclose only what they know to be their second-best embodiment, while retaining the best for themselves.
Confusing Ambiguity with Breadth
While a broad claim is not necessarily ambiguous merely due to breadth, the reverse is problematic. Ambiguity does not lead to a broad scope of protection in a patent. This is a issue even experienced patent attorneys wrestle with and sometimes get wrong. By far, the most common source of trouble is the use of functional language or results-based claiming to try to obtain preemptive exclusive rights over significantly more than what was actually invented. This is one of the trickiest and most contested aspects of patent law and policy, so any brief discussion is hardly comprehensive.
Patent law looks to what is generally understood by given language. Using coined terminology and nonce words — often with vaguely functional connotations — without providing a sufficiently clear definition sometimes leads to impermissible ambiguity. Generic structural terminology as understood in a given technological field is often not the same thing as coined terminology not adopted into use generally in that field. For instance, the coined word “parkulator” does not convey any accepted structural meaning sufficient to use that term in patent claims (without a sufficient express definition). All too often, patent language is specifically drafted to avoid the use of generally-understood terms, which invites ambiguity problems. But you cannot benefit from avoiding accepted meanings if others cannot reasonably determine the scope of a claim due to intentional ambiguities.
There are many other examples as well, sometimes the result of errors and inconsistencies. For instance, if a claimed inventions rests on a parameter like an angle between two things, or a specific concentration of an ingredient or chemical element, or performing a process at a particular pressure, then it may be important to explain — consistently — how such parameters are measured or evaluated. The percentage of a material by weight or by volume might be quite different depending on the density of all the materials involved. Or the pressure might be measure in relative or absolute terms. And the location or direction in which an angle is measured might matter. Similar issues can arise through poor English translations too, which are treated as intentional choices. So translating a non-English word as a “spoon-digger” rather than a “backhoe” can be problematic.
Not Understanding Terms with Special Legal Meaning
There is a concept, sometimes referred to as the Dunning-Kruger Effect, that those who are incompetent in a given area tend to be ignorant of their own incompetence. In patent law, certain language has special legal significance. Rather than being given their ordinary, everyday meaning, certain words in certain contexts can be legal “terms of art” that have a special meaning. The paradox is that unless these special meanings in patent law are known, they might be inadvertently or unintentionally invoked.
Perhaps the most frequent errors of this sort arises with means-plus function claiming (35 U.S.C. § 112(f)). Under this format, an element of apparatus is claimed as “means for…[performing a stated function]” or “[functional descriptor] means for…[performing a stated function].” This type of claiming is currently permitted in the U.S. but is given a special interpretation: it literally covers only the disclosed corresponding structure, material, or acts, plus their known equivalents. Such an interpretation might be narrower than intended. It also might raise other problems if the corresponding structure is not clearly identified and disclosed.
Even patent attorneys can struggle with means-plus-function claiming. Courts have (somewhat controversially) said that if a claim limitation is drafted in the same format as a means-plus-function limitation and merely replaces the term “means” with a nonce word or generic placeholder like “module”, “mechanism”, “element”, or “device”, then a means-plus-function interpretation may still apply. Speaking in practical terms, claim limitations that rely too much on non-structural functional language might be interpreted as means-plus-function claiming.
Irrelevant Disclosure
Including a lot of unnecessary information just because it is available can be another problem. It wastes time and effort, and time is money when preparing patent applications. It can also obscure what is important and lead to longer (and more expensive) prosecution and examination after initial filing. Of course, knowing what sort of information is relevant and what is not is something that requires knowledge and experience. It can also be a matter of understanding the closest prior art, which is the next point.
Not Understanding the Closest Prior Art
Patentability largely depends on an invention being novel and nonobvious over what was already known. So, the catch is that to understand what is patentable it is unavoidably necessary to understand what is the closest prior art. Most of the time, that requires conducting a patentability search and analysis. However, applicants often wish to avoid the expense of a patentability search. This often leads to false economy, by requiring extensive post-filing efforts and expense to mitigate the problem of having not prepared a better initial application.
Knowing the closest prior allows a better patent application to be prepared — one that articulates what feature(s) of the invention differ from the closest prior art (and why that matters). For instance, a patentability search and analysis might suggest that additional technical information (another data table, figure, etc.) needs to be gathered for inclusion in a new application in order to sufficiently explain why the invention makes a patentable improvement. This may be the case where the prior art already achieves a similar result but in a different way, or where the prior art includes all the same parts but has them arranged or connected in a different way.
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 certain requirements and interpretive frameworks that apply U.S. design patent applications that may not be intuitive. Many of these U.S. standards also differ significantly from the rules the apply to industrial design registrations in other countries. What follows is a guide to some common mistakes and misunderstandings around design patents and applications.
Additional information about acceptable practices for design patent applications can be found in the U.S. Patent & Trademark Office’s (USPTO’s) design patent application guide and in the Manual of Patent Examining Procedure (MPEP) Chapter 1500.
“Engineering” Style Drawings Treated Unfavorably
Designers may create computer-aided drafting (CAD) drawings to document their designs. These often follow engineering conventions, including the use of “tangent” lines to show the boundaries of a curved surface. However, U.S. design patent practice relies on the use of surface shading lines or stippling . This is any entirely different style and approach than familiar engineering standards. But there is no single explicit rule or statute about the permitted format of shading lines in design patent drawings.
Shading lines or stippling that contrast with the rest of a drawing are used to show curves, tapers, and other three-dimensional (3D) contours in design patent drawings. The arrangement and variable spacing of straight shading lines is commonly used to indicate the character of curvature or contouring. Shading lines that are not straight may also be permissible. Surface shading lines can be broken/discontinuous and/or light/thin to differentiate them from lines indicating surface ornamentation and/or the ornamental shape of an article itself. Although they must be used sparingly, with as few in number as practicable.
Other characteristics can also be represented by shading lines. For instance, equally spaced shading lines arranged parallel to each other are used to indicate flat surfaces. Shading lines or stippling can be used to distinguish open areas (like holes) from solid material as well. Also, oblique line shading is used to show transparent, translucent, and highly polished or reflective surfaces, such as a mirror. Elements visible behind transparent/translucent surfaces should be shown in light, full lines rather than in broken lines.
The following is an example used in the USPTO’s design patent application guide to illustrate straight, parallel shading lines with their spacing using to show curved edges of a sink. These shading or contour lines are discontinuous, each having a long unbroken segment plus a short, dot-like segment slightly spaced from an end of the long segment. In this example, other discontinuous shading lines are used to illustrate flat surfaces too.
USPTO example of use of shading lines in design application drawings
The following example is also from the USPTO’s design patent application guide, and shows a wheel hub with a combination of shading lines and stippling. The shading lines indicate contouring/curvature and well as flat surfaces. Some of those shading lines are discontinuous while others are continuous but light lines. Contrast in materials or surface texture may be shown by using line shading in one area and stippling in another. In this example, the stippling can show matte surfaces in contrast with highly polished surfaces shown in line shading.
USPTO example of use of shading lines in design application drawings
The following is an example of non-linear (curved) shading lines used to illustrate 3D curvature of a vehicle mirror. These shading or contour lines are discontinuous to distinguish them. These types of shading lines are appropriate for illustrating more complex 3D shapes. In this example, broken (dashed) line(s) further illustrate the boundary of the claimed design, meaning that only a portion of the depicted article is part of this claimed design.
The following examples are drawn from a case about alleged infringement of two design patents covering a trash can and a recycling bin. Red arrows indicate lines whose meaning was disputed by the parties. The court construed the patents’ engineering-style drawings with curvature boundary tangent lines to mean visible ornamentation in the form of seams, paint, or something else that appears as actual lines on the trash can or recycling bin rather than merely conveying the boundaries of 3D contours where they transition to flat surfaces.
Annotated verisons of FIG. 1 of U.S. Pat. No. D644,807 for a “Slim Open Trash Can” (left) and FIG. 1 of U.S. Pat. No. D729,485 for a “Dual Recycler” (right) with red arrows and blue circles indicating disputed lines in Simplehuman LLC v. iTouchless Housewares and Prods., Inc., 506 F. Supp. 3d 830 (N.D. Cal. 2020)
The court reasoned that because the purported drafting technique in the examples above made it impossible to distinguish contour changes from ornamental lines, and because such ambiguous usage raises indefiniteness concerns that should be discouraged, a “plain meaning” interpretation was adopted, finding that the disputed lines are lines (that is, ornamental features in the form of seams, paint, or something else that appear as actual lines on the articles). The patentee’s arguments that the disputed lines were shading or contour lines merely meant to demonstrate the general shape of the trash can/recycling bin were rejected.
The case later settled, and was dismissed without a final ruling on infringement. But the patentee would undoubtedly have lost under the court’s construction that the disputed engineering-style lines meant visible ornamental lines — neither the patentee’s own products nor the accused products had any features that resembled visible lines in the relevant locations.
The Title is Limiting
U.S. design patents are directed to ornamental features of useful articles. Significantly, they cover only particular articles that embody the claimed design, and not simply a “view” or “look” in the abstract (as is the case for industrial designs in some other jurisdictions). The words of the claim — which always says “as shown and described” — will limit the scope of the exclusive patent legal rights. Courts have said that the title of a design patent is limiting, where it names a particular type of article. And that is the case even if the drawings of a design patent do not illustrate any particular article. So the title and other words in a design patent application should be chosen carefully.
In the example reproduced above, a figure from a design patent shows a “Y”-shaped, rattan wickerwork-style pattern formed by a web of material. None of the figures in the patent illustrated the design being applied to a particular article, only the pattern formed by a portion of material shown in isolation. But the title of the patent is “Pattern for a Chair”. A court ruled that the patent’s claim was limited to a pattern for a chair, as specified in the title, and a lawsuit against a seller of a basket (not a chair) with a similar pattern making up the basket/bin walls was dismissed for failure to state a plausible claim of design patent infringement.
Sole figure in App. Ser. No. No. 29/491,550 (now U.S. Pat. No. D979,060) for a “Lip Implant”
Image of prior art “stump” art tool considered in In re SurgiSil, L.L.P., 14 F.4th 1380 (Fed. Cir. 2021)
Limits on claim scope by the title or other text might help distinguish prior art. In the example images above, a design patent claim for the “ornamental design for a lip implant” was limited to lip implants. A court said that a prior art tool made of tightly spiral-wound paper called a “stump”, used by artists for smoothing and blending large areas of pastel, charcoal, or pencil, was directed to a different article than the claimed lip implant. Therefore, the prior art “stump” did not affect the novelty of the claimed design even though their shapes were essentially the same. However, an older case held that if the prior art discloses any article of substantially the same appearance it is immaterial what its use was, so this lip implant decision is in tension with that precedent.
The title of a design application can also potentially limit the prior art available as “comparison” art in a later three-way comparison of the claimed design, an accused product, and the closest prior art for an infringement analysis. Such a comparison can highlight differences (or similarities) in the overall appearance that might not otherwise be apparent to an ordinary observer. To qualify as comparison prior art, a notable court decision said that the prior-art design must be applied to the article of manufacture identified in the claim of the asserted design patent.
Partial Claims Are Permitted
It is possible to depict an article while using a partial claim that addresses the design of only a portion of that article. Structure that is not part of the claimed design, but is considered necessary to show the environment in which the design is associated, may be represented in the drawing by broken lines. This includes any portion of an article in which the design is embodied, or applied to, that is not considered part of the claimed design. For instance, when the design is for surface ornamentation, the shape of article to which the design is applied can be shown in broken lines.
Moreover, unclaimed things may be shown in broken lines for the purpose of illustrating the environment in which the article embodying the design is used. For instance, a claimed design might be for the hood of a truck, only, with the rest of the truck shown in broken lines as unclaimed environment.
Unclaimed subject matter must be described as forming no part of the claimed design or of a specified embodiment thereof. A boundary line may be shown in broken lines if it is not intended to form part of the claimed design. Applicant may choose to define the bounds of a claimed design with broken lines when the boundary does not exist in reality in the article embodying the design. It would be understood that the claimed design extends to the boundary but does not include the boundary.Unclaimed subject matter must be described as forming no part of the claimed design or of a specified embodiment thereof. In this situation, broken (dashed) lines are used to define the boundary of a design patent application claim. This practice in the U.S. departs from that of some other countries where partial claims are not permitted.
Additionally, structure that is not part of the claimed design, but is considered necessary to show the environment in which the design is associated, may be represented in the drawing by broken lines. This includes any portion of an article in which the design is embodied, or applied to, that is not considered part of the claimed design.
USPTO Will Often Not Permit Changes in Claim Scope by Amendment
One controversial aspect of U.S. design practice is that changes in claim scope are usuallynot permitted. While partial claims are permitted in design applications, and while claim amendments in utility patent applications are routinely permitted (even to remove limitations), since 2013 the USPTO does not ordinarily permit lines to be changed from solid to broken (dashed) to broaden the claim, or the reverse to narrow the claim. Instead, applicants are often forced to file a separate application with a different claim scope. While examiners have some discretion to permit drawing changes, such as to fix discrepancies by changing lines to broken ones, and the text of disclaimers or statements in an appendix might have some impact, those things are not certain to be effective under current law and practice.
This practice of precluding changes in design application claim scope extends an already controversial position taken by a U.S. appeals court that reads a so-called “written description” possession requirement into the U.S. patent statutes (relating to enablement) against their plain language and grammar. Note that there is also a clear incentive for the USPTO to require new filings instead of amendments in order to generate more filing fees.
Multiple Embodiments are Sometimes Permitted
It is possible to include multiple embodiments in a single U.S. design application. However, restriction practice still applies and may require dividing different embodiments/designs into separate applications. Because design applications can have only a single claim, multiple embodiments must be patentably indistinct to remain in a single case.
On the one hand, because design patents have a 15-yearterm from grant, later-filed and later-granted divisional applications will expire later. This might be desirable for some patentees. On the other hand, a restriction determination also has an impact on the scope of exclusive rights. For instance, if the applicant elects one embodiment but declines to pursue an unelected embodiment in a divisional application, the unelected/abandoned embodiment will effectively be surrendered and dedicated to the public. These considerations emphasize the need to think through the implications and potentially commit to filing multiple applications when multiple distinct design embodiments are involved.
Drawings Must be Definite and Enabling
Drawings in a design patent application must be consistent with each other. Discrepancies between different views can create indefiniteness and/or lack of enablement issues. For instance, if certain features are shown in one view but omitted in another, this may make it unclear what design is really being claimed. The use of inconsistent drafting techniques in different drawings can also lead to similar concerns. For instance, discrepancies in the use of shading lines, stippling, and/or broken lines can detract from required clarity. Particularly for highly complex illustrations, it is important to carefully review the drawings to ensure that they are consistent.
A frequent issue is when there are holes, cavities, protrusions, or the like and their depth or height is potentially uncertain in plan or elevation views. Sometimes examiners may require cross-sectional views to show the depth of such features. But clarifying sectional views cannot always be added after initial filing without impermissibly adding new matter–instead a new continuation-in-part application might be necessary.
Mixing Photographs and Line Drawings is Not Permitted
Black and white line drawings are preferred and ordinarily required in U.S. design applications. However, photographs can sometimes be used, particularly where there is surface ornamentation that is not reproducible in line drawings. Such photographs can have added lines, such as broken lines to indicate a boundary of the claimed design. But it is not permitted to have both photographs and line drawings combined in a single design patent.
It is possible to include a mix of photographs and line drawings in a new U.S. design application, which might have significance for priority claims or divisional filings, but the drawings must be amended and limited to one or the other type before grant. If photographs are included as informal drawings in a new application, then a disclaimer included in the specification or on the photographs themselves should be used to disclaim any color, surface ornamentation, logos, written matter, etc. that forms no part of the claimed design.
Color Can Be Claimed
Use of color presents many opportunities for procedural problems and well as unintended impacts on the scope of claimed design patent rights. Color can be claimed in a design patent application. However, the use of color drawings (including color photographs) requires filing a petition and paying a petition fee to have color drawings accepted. Also, there is a requirement that the specification include the following statement:
“The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.”
Instead of using color drawings, an alternative is to use black & white line drawings lined for color in accordance with the drawing symbols in MPEP § 608.02 (and reproduced in the USPTO’s design patent application guide). Essentially there are particular line patterns usable to represent specific colors. If this is done, the application must state “The drawing is lined for color.” The specific colors lined in the drawing(s) may also be identified in the specification for clarity, as a kind of legend that explains the lining patterns from MPEP § 608.02.
Also, if color photographs are initially submitted as informal drawings (to later be replaced with formal drawings) and the applicant does not consider the color to be part of the claimed design, a disclaimer should be added to the specification as follows: “The color shown on the claimed design forms no part thereof.” The USPTO will consider color an integral part of the disclosed and claimed design in the absence of a disclaimer filed with the original application.
Appendices Are Permitted
Although not specifically discussed in MPEP Chapter 1550, the USPTO’s design patent application guide, or reported court cases, the USPTO currently permits design applications to include an appendix. The appendix is never published in granted design patents. An appendix can include text statements, such as a purported reservation of the right to change solid lines to broken lines or vice-versa, additional views or embodiments, which could be in the form of line drawings, photographs, or both. The main purpose of an appendix is to potentially provide support for a greater range of amendments and/or continuing applications after initial filing.
Applicants will sometimes not include an appendix because they are unaware that it is possible to do so. After all, the USPTO does not expressly discuss them in any of its regulations or procedural guidelines. Courts have not definitively ruled on the permissible use of design application appendices, however. Yet design examiners generally allow applicants to include and rely on them and generally do not object to their use.
Functional Aspects Are Not Protected
Sometimes design patent applicants wrongly believe that a design patent will cover functional aspects or a general idea. They do not. The type of subject matter that can be claimed in design patents is different from utility patents.
Design patent protection is limited to protection of ornamental aspects of a useful article. Purely functional aspects or a broader general design concept are not protected. Also, anything dictated by function, no matter how aesthetically pleasing, cannot be protected by a design patent. Where this becomes less clear is where design features are only partly functional, and they contribute at least some minimal ornamentation to the overall design. In those situations, the functional aspects limit the scope of protection in the overall design without completely precluding protection of the minimally ornamental aspects.
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.
An important first step in obtaining patents is to identify potentially protectable inventions. The process of gathering up candidate ideas that might be the basis for new patent applications is sometimes termed invention harvesting. But that is an informal term. It generally connotes affirmatively investigating research and development efforts to draw out aspects that might be patentable. The following discussion explains when this sort of effort is worthwhile and how to go about it.
Who Should Consider Invention Harvesting?
There are two basic requirements in terms of who should consider invention harvesting, plus an important practical consideration. The first basic requirement is some desire to pursue a patent. Only companies that might want to pursue patents need to consider invention harvesting. For instance, budget constraints or company policy might mean that patenting is unlikely. The second is activity that comes reasonably close to what is potentially patent-eligible and patentable. For instance, if there is absolutely no technological or engineering activity underway, efforts to identify inventions might not be worthwhile until circumstances change.
In practical terms, however, invention harvesting is typically a process that takes place within companies of a significant size. When there are multiple people or departments with different responsibilities, there is the possibility that inventive activity might be taking place somewhere that has not yet come to the attention of other people who make decisions about patenting. The basic idea is that “invention harvesting” is a proactive way to bring people or teams with different responsibilities together to help them meet shared or company-wide objectives. It rests on an understanding that simply expecting scientists and engineers to step forward when they believe they have an important invention may not capture all patentable inventions.
When Should Invention Harvesting Take Place?
Generally speaking, invention harvesting should be considered around the time that inventions are sufficiently developed to be “ready for patenting” but prior to any public disclosure or commercialization.
“Ready for patenting” means the invention is sufficiently developed that the inventor(s)—with the aid of a patent attorney—can describe how to make and use it. Vague goals and undeveloped business objectives are not enough if they amount to little more than a plan or hope to invent something in the future. The same goes for high-level business plans to meet some kind of customer demand without any definite ideas of how to achieve any specific results—those things are not sufficient. But anything that has been “reduced to practice” in the form of a working prototype is likely sufficiently developed, even if there still is ongoing testing and development work.
There can be public disclosure, public use, and on-sale bars to patenting. This makes it important to consider any potential inventions before any part of a new product is disclosed to someone else, from potential customers to potential business partners or even industry trade groups. This is true even though some countries, like the U.S., have patent filing grace periods.
Key product development stages or milestones, such as engineering “design reviews”, can be excellent times to proactively assess potentially patentable inventions. Also, any planned non-confidential disclosures or sales activities also make good prompts to consider patenting before those disclosures or sales activities take place. But there is no single right time to consider patenting. In fact, it may be a question that needs to be revisited over time.
What Should Invention Harvesting Activity Look For?
Of course, patentable invention might arise at different levels of generality and at different times during development. A product as a whole might not be patentable but specific features of it might be. Those narrower patentable aspects might not be identifiable at the outset of new product development and may only arise later on after considerable work has been completed. On the other hand, investment in research & development (R&D) is no guarantee that any patentable invention will arise. But the catch is that if you sometimes will miss patentable inventions unless you look for them. From that perspective, it is not a waste of effort to consider patentability even if nothing patentable is identified yet.
How Should Invention Harvesting be Conducted?
Some key foundations of invention harvesting are education, communication, and having resources in place to retain and act upon information gathered.
Education starts with emphasizing a desired to consider patenting. It also means cultivating, or bringing in by way of retaining an outside patent attorney, a reasonable awareness of patent law. Inventors might not have a good understanding of patent law and therefore may misunderstand what can (and cannot) be patented, for example. Education also means informing patent counsel about what kind of patenting strategy is desired from a business perspective. Some inventions might be more challenging than others to patent. There is an element here of establishing a comfort level with risk tolerance: do you want to aggressively pursue patent applications including ones that might not succeed, or take a more conservative approach and only file patent applications that seem to have a high probability of success?
Communication is about bringing the right people together to talk about potentially inventive activities. Sometimes, inventors may be very humble or shy and not willing to step forward and promote their own work. As another example, an invention may be patentable even if its inventor does not subjectively consider it to be “important”, such as where the inventor applies an idiosyncratic standard of “importance” that does not align with current laws around patentability. Sometimes having an explicit “invention harvesting” session with patent counsel is worthwhile, in which potential inventors talk about their ongoing work in an open-ended way to try to tease out potentially patentable inventions.
Resources like having a plan to document inventions and giving people or committees responsibility to approve patenting are really the lase piece of the puzzle. Having some sort of “invention disclosure” form to document potential inventions in writing is worthwhile. Such a form can not only provide a written record of the substance of a potential invention, it can also collect supporting information. Such supporting information can include the names of the potential inventor(s), any planned commercial release or public disclosure date(s), relationships between the invention and business initiatives, and other information that can be useful when making patent filing decisions and reporting on company activities.
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.
A file wrapper, synonymously called a file history, is the written record associated with a given patent or trademark application and any resultant granted patent or trademark registration. It is the official record for a given matter. Generally, the file wrapper includes more information than is formally published by a patent or trademark office in patents, published patent applications, or trademark registration certificates.
The sorts of materials maintained in file wrappers, the period of time those materials are retained, and the level and ease of public accessibility to them varies by jurisdiction. For instance, in the USA, patent application information is kept confidential initially and generally only made publicly available for published applications and granted patents, with pending applications normally published 18 months from the earliest filing or priority date (subject to potential non-publication requests). (35 U.S.C. § 122).
How & Where to Obtain a File Wrapper
In the past, file wrappers were only available as hard copies in on-site storage at official offices. Today, many patent and trademark offices make at least some file wrapper contents available online—though whether online versions are the official ones or not and whether the online versions are complete or not are questions that can vary by jurisdiction. File wrapper materials are generally also available as certified copies that must be specially ordered (and may have to be physically mailed). Usually a given file wrapper must be obtained from the relevant patent or trademark office that maintains it, although centralized file wrapper access for a few global patent offices is available.
The U.S. Patent & Trademark Office (USPTO) has “Patent Center” and Trademark Status and Document Retrieval (TSDR) online portals. Very old materials are not always available through these portals. Moreover, some materials are not accessible through Patent Center to the general public, like copies of non-patent literature. The USPTO also has a separate Certified Copy Center that allows officially-certified copies of file wrappers or specific documents from them to be ordered, upon payment of required fees. Certified copies of file wrapper may include materials that are not otherwise publicly available, and include official seals and signatures attesting to their authenticity.
The European Patent Office (EPO) has a European Patent Register with file wrapper information. These materials are also accessible via the Espacenet portal, by clicking the “Register” link within a given record.
There are also separate systems for file wrappers for PCT international patent applications and Madrid Protocol trademark registrations. These are the Patentscope and Madrid Monitor online portals maintained and administered by the World Intellectual Property Organization (WIPO). It is also possible to order certified copies of Madrid international trademark registration materials from WIPO, or for applicants to order certified copies of PCT applications from individual PCT receiving offices.
Additionally, Global Dossier portals provide access to file wrapper contents from a number of the most active patent offices worldwide, together with machines translations. Global Dossier has gone by other names in some jurisdictions, like “One Portal Dossier” in Japan and South Korea. Because of the availability of machine translations, these portals can be highly convenient for gathering information about foreign patent applications in other languages. But some documents may not be immediately available through these portals, either due to technical glitches or database update lags.
Why Might You Need a Wrapper?
There are many reasons a file wrapper might be consulted. For instance, they can provide a record of the prosecution history that may inform the status or interpretation of something related to a given patent or trademark. A record of official actions like rejections/refusals and/or applicant amendments or arguments might be found in the file wrapper. Particular documents within a file wrapper might be relied upon for various purposes, or might be needed for submission in other contexts. For instance, in U.S. patent law, the file wrapper might be relied upon for claim construction, doctrine of equivalents analysis, inequitable conduct inquiries, and more.
File wrapper materials in informal, online formats might be sufficient for many purposes, and may be free and easy to access. Information materials might be used for competitive intelligence purposes or as a reference example for work on an unrelated matter, for example. Certified copies or an entire file wrapper, or one or more selected documents from it, might be required for certain formal uses, such as to make priority claims in foreign applications or to be relied upon in legal proceedings where authentication of the materials is important.
The legal important of a file wrapper often depends on the substantive law of the relevant jurisdiction. Under U.S. patent law, prosecution history estoppel or prosecution disclaimer found in a file wrapper might arise and bind the patentee. But many other jurisdictions do not have any such patent prosecution estoppel doctrines, making file wrappers less formally significant. And, moreover, the USPTO does notaccept formal file wrapper estoppel in trademark matters.
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.
For patents and trademarks, the term “prosecution history” refers to the back and forth between an applicant and the patent or trademark office. It includes submissions by the applicant, starting with an original application and extending though any amendments or arguments the applicant might later make during official examination of the application. It also encompasses official communications, like office actions, and the particular rejections, objections, refusals, and other notifications that may be contained in them. Oral communications like interviews are a part of it too.
But “prosecution history” refers to more than just a set of documents or particular communications. It is a blanket or umbrella term that refers to all the actions and events involving the patent or trademark office from the time a new application is filed to through grant or registration and even beyond that to post-grant or post-registration actions involving corrections, maintenance or renewals, and the like. So, even if a particular document is purged or deleted or never made part of the permanent record, such a document and the events surrounding it are still part of the prosecution history.
Prosecution histories are important for many reasons. As reflected in “file wrappers,” they are often consulted to understanding the status of a pending application or of a granted patent or issued trademark registration. They can provide insight into why a patent or trademark registration was issued in a particular form, or why a application was abandoned. Sometimes events or materials from the prosecution history of a given patent or trademark registration can even impact the scope or validity of enforceable legal rights.
The prosecution history tends to matter most where prosecution history estoppel or prosecution disclaimer might arise and legally bind the applicant later on. In the U.S., it tends to be more important for patents than for trademarks. Many other countries have different laws that make prosecution history less consequential.
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.
The U.S. Patent & Trademark Office (USPTO) makes granted U.S. patents and published U.S. patent applications publicly available. Patent Public Search is its open-access patent searching platform, available online to anyone free of charge. It exists with two different interfaces: Patent Public Search Basic (PPUBS Basic) and advanced search. Both allow U.S. patents and published applications to be searched simultaneously. Coverage is limited to only U.S. patent documents.
Screenshot of the USPTO’s Patent Public Search landing web page, with links to the “Basic Search” and “Advanced Search” interfaces
There are official training guides and frequently asked questions (FAQs) available for Patent Public Search. These provide detailed guidance about how to use the tool, particularly the advanced features. What follows are basic explanations of how to fetch individual patents from the USPTO and find either PDF images or selectable/copyable text from U.S. patents and published applications.
Screenshot of the USPTO’s Patent Public Search FAQs
The Basic (PPUBS Basic) search interface allows granted U.S. patents and published patent applications to be fetched by number (“Quick Lookup”), and allows some keyword-based searches (“Basic Search”). But it returns only PDF copies.
Screenshot of the USPTO’s PPUBS Basic search interface
This interface is simple and mostly self-explanatory. Although, if desired, consulting the USPTO’s basic search interface overview may be helpful. One important thing to note is that the search input fields allow only a single word or number in each and a maximum of two keywords can be used. So, for searches using two distinct keywords, it is necessary to use different input fields for each of them and to select a Boolean operator (AND, OR, or NOT).
Screenshot of an example search result for a “Quick Lookup” of U.S. Pat. No. 10,000,000 via the USPTO’s PPUBS Basic search interface
The Basic interface is most useful for fetching PDF copies of granted patents and published patent applications when the patent or publication number is known. The trade-off is that its functionality is rather limited for subject-matter searches and “full text” is not available for returned results.
Using the Advanced Search Interface
As the name implies, the advanced search includes much more advanced search functionality than the “Basic” interface. However, the advanced interface is highly esoteric and non-intuitive. It may not even display properly on all computers. For instance, primary the input field near the upper left sometimes appears hidden when the tool is opened on computers with small display screens, like laptops.
Screenshot of the USPTO’s Patent Public Search Advanced Search interface, showing the results of a search for U.S. Pat. No. 10,000,000 using the “.pn.” field code
The Advanced Search interface allows queries of up to three distinct databases simultaneously:
US-PGPUB — containing U.S. pre-grant patent application publications from March 2001 onward;
USPAT — containing full-text granted U.S. patents from 1970 onward plus allowing classification and patent number searching from 1790 onward; and
USOCR — containing text-searchable optical character recognition [OCR] scanned pre-1970 U.S. patents
Fetching a particular patent or published application by number is surprisingly difficult with the “advanced” interface. Use of the “.pn.” (for patent number) code is highly unforgiving and the period at the end is required. The USPTO has said it is possible to manually type in the URL https://ppubs.uspto.gov/pubwebapp/external.html?q=(00000000).pn. and replace “00000000” with the desired patent number in order to reach it directly though an “external search”. Use leading zeros to fill a 7-digit entry if the patent number is 6 or less digits (for example, “0654321”). And do not forget the period at the end! Unfortunately, Patent Public Search modifies this URL as displayed in a browser once it is visited so there is no simple way to bookmark it. Also, expect some frustration because these “external search” URLs do not seem to consistently work (especially if Patent Public Search was previously opened in your browser).
Annotated screenshot of Patent Public Search Advanced Search Interface “Document Viewer” “T / [camera icon]” button to toggle between text and PDF image views
The advanced interface is currently the only way the USPTO provides “full text” of published patent documents. PDF versions are also available by clicking the “T / [camera icon]” button at the top left of the “Document Viewer” panel that normally appears at the right-hand side of the screen along with the text (annotated in the figure above). Toggling that button allows switching between text or PDF image displays of a given patent document.
Other commands are available by clicking on rather confusing and esoteric icons in the “Document Viewer” panel, such as various quotation mark buttons that allow forward and backward searching of citations. Note that references cited listed on the front page of granted patents are omitted from the “full text” display in Patent Public Search, meaning that “full text” is not truly available for all text of a given patent document. Foreign and non-patent literature citations will appear only in the PDF image of the granted patent and thus are not selectable to copy-and-paste them.
Annotated screenshot of Patent Public Search Advanced Search Interface “Document Viewer” quotation mark buttons to forward and/or backward search U.S. patent documents from the “References Cited” section of a granted U.S. patent
If you plan to conduct extensive searching by subject matter, using keywords and/or classification codes, you may want to consult the USPTO’s official Patent Public Search training guides and FAQs as well as the “Help” menu tab inside the interface’s “Search Results” panel. The “Search Overview” Quick Reference Guide and the FAQs may be the most useful places to start, followed by “Searchable Indexes” (that is, field code) list and the “Help” menu tab inside the interface. Some content found in the “Help” menu tab of the “Search Results” panel inside the interface (such as explanations of proximity operator syntax) does not appear anywhere else at present—quite unhelpfully!
Also be aware that Patent Public Search uses search string syntax that is unlike commercial patent searching tools. Familiarity with other search tools (other than the USPTO’s old PubEAST and PubWEST tools) will not translate into any understanding of how to use Patent Public Search.
Alternatives: Patent Center, International Open-Access Tools, and Proprietary Tools
An alternative way to reach a particular U.S. patent or published application in USPTO databases is to utilize the Patent Center interface. Patent Center’s main interface provides a simple query field where you can enter a U.S. patent or published U.S. patent application number. Once the results of a given query appear on screen, there are links available to the Patent Public Search text versions of the given published application and granted patent (if any) under Patent Center’s “Application Data” tab. The button with the “T/[camera icon]” label can be clicked to toggle between a text view and a PDF image of the patent document in Patent Public Search. While navigating to patent documents through Patent Center requires many clicks, using it may be easier than using Patent Public Search.
However, links to patents and published applications in Patent Center are often broken or non-functional. This is a major problem. And Patent Center intentionally blocks copy-and-paste operations to copy patent or publication numbers into a different database that does function properly. The system has also been plagued by a lack of capacity. Rather cryptic error messages (usually colored red) may appear when attempting searches on the platform. These errors reflect that the computer infrastructure on which Patent Center runs has reached a capacity limit, forcing users to re-run searches. This can be seen as a form of under-funding the Patent Center infrastructure.
Another alternative for fetching PDFs of U.S. patents and published patent applications is to use a privately-operated site or a foreign patent office site with international coverage. There are many proprietary patent searching tools that require a subscription. But there are also open-access or semi-open-access tools available online that contain at least U.S. patent documents, including:
Compared to many other online patent searching tools, Patent Public Search has substantial usability flaws. Although it has more coverage and capabilities than it predecessors PatFT and AppFT, it is much less user-friendly and eliminated some features of the old systems. Tabbed browsing to open multiple documents at once is prohibited by the “advanced” interface, for instance. Also, the “advanced” interface frequently has long delays to load or fails to load, and the “basic” interface often stalls without loading patent PDFs—making them effectively inaccessible. These are faults with the USPTO’s computer infrastructure and the design of these tools. Even compared to other open-access platforms, like Espacenet, Patent Public Search is harder to use. It is even inferior in many ways to the “Delphion” tool from the early 2000s (which was converted into one of the leading proprietary platforms and is no longer open-access).
Proprietary searching platforms are still generally the best option. Although subscription fees will be prohibitive if you only perform patent searches occasionally.
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 U.S. Patent & Trademark Office (USPTO) requires that non-provisional patent applications filed on or after January 17, 2024 be submitted electronically in Office Open XML “DOCX” file format in order to avoid a non-DOCX official surcharge. This means applications can still be filed electronically in PDF format, or by paper, but doing so will require payment of an additional official fee that varies according to the applicant’s entity size (initially $400/$160/$80 for large/small/micro entities).
What Types of Applications Must be in DOCX Format?
The DOCX filing requirement and non-DOCX surcharge currently applies only to the following U.S. patent applications:
Utility patent applications (non-provisional) under 35 U.S.C. § 111(a)
Includes direct U.S. filings with a Paris Convention foreign priority claim
Includes PCT “bypass” applications
However, the non-DOCX surcharge currently does notapply to the following types of U.S. patent applications:
Provisional patent applications
Design patent applications
Plant patent applications
PCT national phase entries
Additionally, only certain portions of an application are covered by these requirements. In order to avoid the non-DOCX surcharge, the specification/description, claims, and abstract must all be in a compliant DOCX format. However, the drawings of an application do not need to be submitted in DOCX format. PDF format can be used for electronic submissions of figures without paying a non-DOCX surcharge.
In an answer to a frequently asked question (FAQ), the USPTO has said that the non-DOCX surcharge applies to U.S. applications filed in a language other than English under 37 C.F.R. § 1.52(d)(1). That is, avoiding the surcharge requires filing a DOCX copy of the non-English original. This approach was not officially announced prior to implementation of the surcharge. Of course, that position is at odds with the USPTO’s justification for implementing the non-DOCX surcharge in the first place, because only the English translation is published.
Potential Problems
When application documents are electronically filed with the USPTO’s Patent Center system in DOCX format, they are “validated” to create a new DOCX file and also converted into another format (PDF) by the USPTO with a proprietary conversion/rendering engine prior to submission. For instance, tracked changes strikethrough and underlining/underscore formatting are automatically removed as part of file “validation”. However, that “validation” and conversion process can produce errors. Yet it is the “validated” DOCX file as modified by the USPTO’s system that is considered the “as filed” version that the USPTO actually relies upon for subsequent actions, and not the DOCX file as originally uploaded. The original applicant-created DOCX file is discarded by the USPTO as part of the “validation” process, meaning the USPTO does not preserve the original source file in unaltered (pre-validation) form. Underlying these concerns is the fact that DOCX format is not platform-stable, and rendering of a given document varies depending on the configuration of the computer that opens it. These aspects of DOCX filing are the major sources of concern.
Experience to date has shown that USPTO-side DOCX conversion error issues are particularly significant for application documents involving:
Embedded mathematical equations created with a word processing program’s built-in equation editing functionality
Embedded chemical formulas created with a word processing program’s built-in formula editing functionality
Pseudo computer code with special indenting having technical meaning or special significance
Data tables, particularly if the table introduces landscape page orientation that varies from other pages with portrait orientation or if there is complex table formatting with special formatting like substantively meaningful indenting within table cells
Text in unusual characters/symbols or fonts, including Greek letters and/or uncommon accent marks with technical significance
Claim autonumbering using automatic numbered list formatting
Document creation using a word processing program other than a version of Microsoft Word® using a Latin-alphabet interface
Document creation or editing with word processing program plug-ins or macros for machine translations, automatic application content population, and the like, especially when such plug-ins lock application formatting or content against further editing
Many of these things are fairly common in patent applications.
The USPTO treats a DOCX version as the definitive record copy, potentially allowing later correction of USPTO-side conversion errors by filing a petition. However, the USPTO has clarified that only the “validated” DOCX file as modified by the USPTO’s systems during the filing process are treated as authoritative and not the applicant’s pre-“validation” source version. The USPTO has also said that petitions requesting a correction more than one year after a DOCX submission will not ordinarily be granted (except that, if applicable, incorporation by reference of a priority application or filing a pre-English-translation version may provide a different, independent basis to request correction more than a year later). This time limit stemmed from the USPTO saying it may discard applicant submissions after one year, retaining only a USPTO-converted/validated file — although a later USPTO rule announcement indicated that applicant-generate PDFs will now be maintained as part of the permanent record and not discarded. There remain some ambiguities and inconsistencies in these USPTO statements, particularly because the USPTO never specifically retracted its statement that petitions filed more than one year after an application is filed will not ordinarily be granted.
The USPTO has permitted a limited opportunity to file a back-up applicant-generated PDF version (“Auxiliary PDF”) of an application filed in DOCX format that can further allow for later correction of USPTO-side conversion errors. However, this Auxiliary PDF submission is being permitted indefinitely, during which time there are no extra official fees associated with submitting an Auxiliary PDF or to petition to correct a USPTO-side conversion error based on such an Auxiliary PDF. And the USPTO has said that the Auxiliary PDF will be retained as part of the permanent record for a given application. However, there is significant effort (and associated time cost) required for an applicant to prepare and file a petition to correct a USPTO error, and there is no guarantee that such a petition will be granted. Indeed, some petitions to correct USPTO-side DOCX conversion errors have been denied and/or have significantly delayed examination.
Another very significant point is that the USPTO has taken the position (first stated in a FAQ answer published only after the surcharge went into effect, then further clarified in a notice in May of 2024) that a preliminary amendment filed on the same day as an application subject to the DOCX requirement must also be in DOCX format. Failing to file the preliminary amendment on the same day as the new application means it will not be treated as part of the original application. This places additional burdens on applicants. For one, it was not until November 13, 2024 that the USPTO’s Patent Center electronic filing system permitted DOCX format preliminary amendments to be filed simultaneously with a new application (!). When doing so, an “Auxiliary PDF” can be submitted that combines the PDF of the original application and the PDF of the preliminary amendment. However, the USPTO has not provided any guidance about its treatment of substitute specifications in DOCX format, and therefore the ability to file those while avoiding the non-DOCX surcharge remains unclear and prone to risks for applicants. Also, the USPTO had for a long time informed practitioners that DOCX amendment filings in Patent Center did not work properly and should be avoided. One reason was that DOCX-format files with “tracked changes” to show amendment mark-ups would be entered thus removing the mark-up indications when submitted to the USPTO. However, as some unspecified time during 2024, and without any prominent announcement, the USPTO changed the functionality of Patent Center such that “tracked changes” mark-ups in DOCX-format files are converted into fixed-formatting underlining and strikethrough. Whether that conversion/rendering process at the USPTO side works properly or produces errors is difficult and burdensome to verify. Therefore, by imposing a non-DOCX surcharge to preliminary amendments tends to increase burdens and risks on applicants.
The possibility of conversion errors arising at all and the burdens of requesting corrections have the potential to negatively impact applicants. Moreover, the increased applicant burden to format DOCX files, proofread converted files, and make separate preliminary amendment submissions is potentially significant unto itself. In effect, DOCX filing saves some effort and expense for the USPTO by pushing or shifting certain very large burdens and risks onto applicants. The supposed benefits to applicants are trivial or meaningless.
Best Practices for DOCX Filing
The following are some suggested practices for DOCX filing. These are meant to supplement or clarify USPTO-provided guidance and frequently-asked-question (FAQ) responses that often serve more as disingenuous “gaslighting” to deny problems filers have encountered and conceal unstated, de facto requirements than to provide reliable, practical, actionable guidance. While a document might be modified shortly before filing to meet minimum requirements or best practices, there can be risks and potential problems associated with doing so, including the introduction of inadvertent errors and potential file corruption. It also may be significantly more time-consuming to later modify an application document for filing than to prepare it in a compliant way from the start.
Top DOCX application compliance tips:
Use paragraph numbering (required), preferably paragraph autonumbering using at least four digits inside square brackets (“[0001]”)
Omit line numbering
Manual paragraph numbering is compliant but makes changes and amendments very burdensome
Often the lack of paragraph numbering in an existing application document is the single most burdensome formatting change required for DOCX filing compliance
Use a supported font, such as times new roman or arial (note that supported fonts are subject to change without notice)
There have been reports that some fonts the USPTO has explicitly identified as being supported are not actually fully supported
While a document-wide font change action can be performed, it may not alter font in embedded equations or formulas, inserted images with text or alphanumeric characters, headers and footers, and the like
Manually number claims with plain text numbers and avoid automatic “list” formatting using word processing program functionality
USPTO systems will sometimes modify claims in numbered list format to number each clause within a claim separately, disrupting intended claim numbering
Use of auto-updating cross-reference fields to indicate claim dependencies sometimes leads to errors in conversion, such as converting all claim dependency references to a prior claim from various numbers to zero (0)
Consider using an inserted image of a complex formula or equation rather than using one generated by a word processing program’s equation editor
Inserted images must have sufficient resolution to be readable
Images should be inserted in-line with text, without text wrapping (text wrapping for images and tables can produce errors with PDF conversions for an “Auxiliary PDF” submission)
Provide figures in a separate document, rather than as pages of the same document containing the application text (specification)
Deletion of pages containing drawings can sometimes produce unintended changes to the formatting of remaining pages in a DOCX file, such as deletion of page numbering, changes to margins, and the like
Use an English version of the proprietary Microsoft Word® word processing program
There are variants of the DOCX format and other nominally DOCX compatible word processing programs will not necessarily create files that will be processed the same way by the USPTO’s proprietary conversion engine
Use of versions of the Microsoft Word® program intended for use with non-Latin character alphabets may render differently on an English-language version of that program, such as removing inter-word spacing. For example, “Balance SBCS and DBCS character(s)” options create warnings in Patent Center about possible reduction of pages
Avoid use of highly customized application templates with macros or uncommon/complex embedded formatting settings
Remove all “content controls”. The presence of “content controls” will make a DOCX file non-processable and unsubmittable. “Content controls” can be made visible by selecting File –> options –> customize ribbon and then selecting the box to make the “developer” tab visible, then, under the (now visible) developer tab, selecting “design mode”; the content controls should now be visible in the document between unique-looking (usually gray) leading and trailing tags.
Simplify! In general, documents with simpler formatting are more likely to be compliant and less likely to result in conversion errors than more complexly formatted ones. Use complex, customized formatting only when strictly necessary or unavoidable
The “.docx” file extension must be in all lowercase letters
The USPTO provides DOCX-compliant utility patent application templates that could optionally be used. There is a basic template and another with essentially all possible application section headings identified. The basic template will like be more appropriate in most situations, with fewer extraneous section headings that are likely inapplicable. However, the use of automatic list claim numbering in these templates can still cause conversion errors and is not seen as actually compliant; thus, manual text-only claim numbering should be used in place of the list-style autonumbering in those templates.
While the USPTO asserts that DOCX file metadata is automatically removed from documents when filed, it is recommended to independently assess and remove any sensitive metadata before filing. Such metadata could relate to document revisions and the like. While such information is not necessarily harmful to an applicant’s interests, its presence in filed documents might possibly increase litigation discovery burdens if a resultant patent is ever enforced. In Microsoft Word, accessing the “File” > “Info” menu and utilizing the “Inspect Document” feature can help identify and then remove metadata. But be careful not to remove necessary document fields like page numbers appearing in footer margins.
One difficulty with identifying errors is that meaningful proofreading requires first uploading the DOCX file to the USPTO’s Patent Center and then reviewing a USPTO-converted file. While Patent Center provides some feedback about certain possible DOCX compatibility issues during the file upload and submission process, such automated feedback will never identify substantive content errors such as unintended changes to numerical values or technically (that is, substantively) meaningful formatting.
An Auxiliary PDF can be filed without charge in addition to a DOCX file, and doing so is recommended. Although it is still a best practice to utilize a reliable DOCX file or pay the non-DOCX surcharge. That is because corrections premised on the contents of the Auxiliary PDF require, at a minimum, significant time and effort associated with formal petitions for correction. Also, in worst case scenarios, such petitions to correct DOCX-related errors might be denied, even if they result from USPTO-side problems. In this sense, Auxiliary PDFs might provide some benefit but are not an ideal or complete solution to the problems posed by DOCX filing.
Non-DOCX Filing Alternatives
In some instances, electronically filing an application in PDF format and paying the non-DOCX surcharge may be more efficient than spending considerable time proofreading converted documents to check for errors. “Last minute”, urgent, or rush filings of applications with potentially problematic equations, formulas, data tables, text formatting, or the like may not allow sufficient time for proofreading, and may suggest PDF format filing and payment of the non-DOCX surcharge.
Filing a PCT application and entering the U.S. via the national phase (perhaps early) is another approach. Because PCT national phase entries are not currently subject to the non-DOCX surcharge, many difficulties are avoided. However, there are different rules and official fees associated with PCT applications that may (or may not) be significant. For instance, for national phase entries, “Track One” prioritized examination is not available and filing a request for continued examination (RCE) requires first submitting all inventor declarations/oaths. And this approach is usually more expensive than paying the non-DOCX surcharge, although some fee deferrals and other additional benefits can arise through PCT filings.
Additionally, if the USPTO’s Patent Center system is unavailable and paper (hard copy) filing via express mail is required to meet a filing deadline or bar date, payment of official non-DOCX and paper-filing surcharges might be necessary.
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.
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