Kate Gaudry, PhD

Case law has defined prosecution laches as an affirmative defense against an infringement assertion. Specifically, the case law indicates a patent that is being asserted is unenforceable when the patentee caused an unreasonable and unexplained delay in prosecution of the patent. Symbol Tech v Lemelson Medical, No. 04-1451 (Fed. Cir. 2005). There is relatively little case law on the specifics of laches. However, in 2021, the Federal Circuit said: “we now hold that, in the context of a § 145 action, the PTO must generally prove intervening rights to establish prejudice, but an unreasonable and unexplained prosecution delay of six years or more raises a presumption of prejudice”. Gil Hyatt v. Hirshfeld (Fed. Cir. 2021). What does this – or might this – mean beyond the Hyatt case?

Typically, patent examiners are the prominent decision-makers controlling whether patent applications are allowed. However, Applicants have the power to change who controls these decisions. For example, each Examiner’s Answer must be approved by a supervisory examiner, so filing an Appeal Brief results in the supervisory examiner reviewing the rejections at hand, the appellant’s arguments, and the examiner’s responses to the appellant’s arguments. (If the supervisory examiner agrees with the appellant, then the application is either allowed or prosecution is reopened with one or more new rejections). So long as prosecution is not reopened, paying the Forwarding Fee subsequent to receiving the Examiner’s Answer results in jurisdiction shifting to the Patent Trial and Appeal Board (PTAB).

Once a rejection by the U.S. Patent and Trademark Office (USPTO) is designated as at least one “final” office action (which typically occurs when the office action is at least a second office action issued after filing), the applicant has the opportunity to engage with a different decision-maker. That is, the applicant can appeal a pending rejection to the Patent Trial and Appeal Board (PTAB), and at least three PTAB judges will then evaluate the rationale provided by the examiner and applicant (referred to as an “appellant” when the PTAB is handling a matter). Alternatively, the applicant can continue to engage with the examiner (which may require filing a Request for Continued Examination and paying the associated fee) or can let the application go abandoned.

On September 2, the U.S. District Court for the Eastern District of Virginia issued a decision granting a Motion for Summary Judgment for the United States Patent and Trademark Office (USPTO) and upholding the Office’s view that AI algorithms cannot be listed as inventors on U.S. patents. The court pointed to the Administrative Procedures Act’s (APA’s) strong deference to final agency decisions, barring any egregious errors. DABUS generated outputs corresponding to (1) a fractal design for food container surfaces that may help prevent stacked containers from sticking together and (2) a technique for controlling the timing of flashing warning lights to help attract attention. Dr. Stephen Thaler (DABUS’s creator and owner) filed patent applications on these inventions that were filed around the world, listing Thaler as the applicant and listing only DABUS as the inventor.

Laches is an equitable defense that may be raised in a patent-related proceeding. If a defending party can show that a patent holder exhibited unreasonable delay that caused prejudice to the defending party, the patent holder may be barred by laches from asserting the right.While the examples of “reasonable” and “unreasonable” delay provided in Symbol Techs. are informative (as are the fact-specific analyses from the other cases), a bright-line test for “unreasonable delay” had yet to be established in the prosecution laches context. That is, until the June 2021 decision of Gil Hyatt v. Hirshfeld (Fed. Cir. 2021). This case pertained to the laches defense raised by the USPTO when Hyatt filed an action under 35 U.S.C. § 145 to obtain four patents subsequent to receiving an affirmance of rejections of various claims at the Patent Trial and Appeal Board (PTAB).