No Enablement of a “Make and Screen” Invention Where Working Examples Do Not Represent Diversity of the Claimed Genus

Feb 24, 2022

Reading Time : 2 min

Claim 1 of the asserted patent in this case was directed to a genus of antibodies defined by two requirements—an isolated antibody or antibody fragment (1) “binds Factor IX or Factor IXa” and (2) “increases the procoagulant activity of Factor IXa.”

In reaching its decision, the court first walked through the Wands factors and found the number of potential candidate antibodies that could fall within the scope of the claim was potentially in the millions, and that screening was required at every “critical step” to determine whether antibodies fall within the claims. The court further found that there were few working examples in the specification and little guidance for how to identify which candidates satisfy the claim. The court deemed the field of antibodies unpredictable, and found the lack of guidance compounded the unpredictability.

Based on its review of the Wands factors, the court dubbed the technology a “make and screen invention,” where suitable antibodies could only be discovered through trial and error. The court discounted the patentee’s argument that the claimed genus contains few antibodies, finding the disparity between the number of possible candidates and the number of claimed antibodies weighed in favor of no enablement. The court reasoned “[t]hat there are fewer needles in the haystack makes the search harder, not easier.”

The court also gave little credit to the patent’s teachings regarding how screening should be performed to identify suitable antibodies, finding that even if such screening had become routine, the teachings still required someone to repeat the same process the inventors used in the first place.

Next, the court noted that although the claims covered antibodies having a wide range of efficacies, there was no indication that antibodies were made or could have been made that achieved the highest levels of efficacy. The court appeared particularly persuaded by two facts. First, the accused infringer took almost 10 years to develop the accused product, which achieved better activity than any antibody disclosed in the patent, but was still far lower than normal levels. Second, the patentee never brought a product to market that embodied the claimed invention. In fact, one of its experts eventually conceded that the patent’s description of therapeutic utility was aspirational, and that it would be difficult or impossible to create an antibody that increased activity back to normal levels.

Finally, the court noted that the working examples in the patent were limited to mouse monospecific IgG or IgM antibodies, which made up only a small subset of the broad antibody structures the claim covered. The court noted that the specification “does not remotely enable the accused antibody,” a bispecific antibody that plaintiff alleges falls within the claims. The dependent claims fared no better—some of them limited the genus to specific structural features for which there were zero examples.

The court concluded that the patent owner merely provided a starting point for further research, but was attempting to claim someone else’s solution.

Practice Tip: Patent Owners should pursue a range of genus claims, some tailored specifically to the working examples in the patent and, in response to an enablement challenge, should highlight any teaching in the patent that provides a shortcut in development, whether it be structural features of relevant compounds or manufacturing techniques that can be used with some expectation of success. For patent challengers, this case reinforces that it can be important to establish the breadth of claims and the degree of trial and error required to identify candidates that fall within a genus.

Baxalta, Inc. v. Genentech, Inc., 1:17-cv-00509 (D. Del. Jan. 13, 2022)

Share This Insight

Previous Entries

IP Newsflash

December 18, 2025

The Federal Circuit recently vacated a $20 million jury verdict in favor of a patentee and remanded with instructions to dismiss the case for lack of subject matter jurisdiction, finding that the patentee did not own the asserted patents at the time it filed suit and therefore lacked standing.

...

Read More

IP Newsflash

December 17, 2025

The Federal Circuit recently affirmed a Patent Trial and Appeal Board decision finding claims that had been subject to an ex parte reexamination unpatentable. As a threshold issue, the court held that IPR estoppel under 35 USC § 315(e)(1) does not apply to ongoing ex parte reexaminations. Accordingly, the Patent Office did not err in continuing the reexamination after issuing final written decisions in co-pending IPRs.

...

Read More

IP Newsflash

December 15, 2025

The District of Delaware recently denied a defendant’s motion to dismiss plaintiff’s demand for enhanced damages based on willful infringement pursuant to 35 U.S.C. § 284, explaining that neither a demand for damages under § 284 nor an accusation of willful infringement amount to a claim for relief that can be subject to dismissal under Rule 12(b)(6).

...

Read More

IP Newsflash

December 9, 2025

The Federal Circuit recently denied a petition for a writ of mandamus that challenged the PTO Director’s reliance on “settled expectations” to discretionarily deny two inter partes review (IPR) petitions. In so doing, the court explained that, while it was not deciding whether the Director’s use of “settled expectations” was correct, the petitioner’s arguments about what factors the Director may consider when deciding whether to institute an IPR or post-grant review (PGR) are not generally reviewable and did not provide sufficient basis for mandamus review here.

...

Read More

© 2025 Akin Gump Strauss Hauer & Feld LLP. All rights reserved. Attorney advertising. This document is distributed for informational use only; it does not constitute legal advice and should not be used as such. Prior results do not guarantee a similar outcome. Akin is the practicing name of Akin Gump LLP, a New York limited liability partnership authorized and regulated by the Solicitors Regulation Authority under number 267321. A list of the partners is available for inspection at Eighth Floor, Ten Bishops Square, London E1 6EG. For more information about Akin Gump LLP, Akin Gump Strauss Hauer & Feld LLP and other associated entities under which the Akin Gump network operates worldwide, please see our Legal Notices page.