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Reasons To Limit Inventor Testimony In Hatch-Waxman Cases

Posted on Feb 15, 2019 in Articles

This article originally appeared in IP Law 360 on February 14, 2019.

Inventor testimony inevitably forms a part of every generic drug company’s case in a Paragraph IV obviousness challenge under the Hatch-Waxman Act.[1] This is odd because the generic defendant in its validity challenge cannot use anything that the inventors did in support of its obviousness case; but, ironically, the patentee/innovator company can.[2] Given the success rate of Paragraph IV obviousness challenges and the legal framework for the obviousness analysis, one can only wonder why this costly practice continues.

All too often, a named inventor will be deposed in a case, and later take the stand, describing their impressive credentials and telling tales of the supposed Sisyphean task and serendipity needed to discover the claimed subject matter. So, generic defendants should carefully consider the usefulness of the inventor’s testimony in its obviousness case.

After all, the convention is to get the “invention story.” Invariably this is reflected in the generic defendant’s Rule 26 disclosures, written discovery, and depositions notices, and is inherent in its case strategy. But the contours of the invention story may be developed via targeted written discovery requests, meaning that inventor testimony is not indispensable. Let us consider some reasons why automatically pursuing inventor testimony can damage a generic defendant’s case.

A common feature of most generic drug cases is the presence of a patent validity challenge based on obviousness under 35 U.S.C. § 103. Hatch-Waxman litigators understand this, and recent statistics indicate that Section 103 defenses dominate in this space.[3] Invalidity positions will of course be patent- and case-specific.

Graham v. John Deere sets forth the obviousness standard.[4] The elements are: (1) determination of the scope and content of the prior art, (2) determination of the level of ordinary skill in the art, (3) differences between prior art and the claim at issue are to be ascertained, and (4) consideration of secondary considerations of non-obviousness.[5] While the obviousness inquiry is a mixed question of fact and law,[6] arguably none of the facts that undergird the inquiry depend on inventor testimony.

The generic defendant should carefully choose its discovery path. The statute provides a signpost often overlooked where it states: “Patentability shall not be negatived by the manner in which the invention was made.”[7] Importantly, the Federal Circuit has held as follows:

[t]he inventor’s own path itself never leads to a conclusion of obviousness; that is hindsight. What matters is the path that the person of ordinary skill in the art would have followed, as evidenced by the pertinent prior art.[8]

The U.S. Supreme Court wrote in its KSR International Co. v. Teleflex Inc. decision,[9] “In determining whether the subject matter of a patent claim is obvious, neither the particular motivation nor the avowed purpose of the patentee controls. What matters is the objective reach of the claim.”

Given the words of the statute, and Supreme Court and Federal Circuit precedent, why do generic challengers still insist on getting the invention story through inventor testimony? Instead, steer the obviousness case away from inventor testimony because the expert witnesses are really where the obviousness case will be won or lost. While a generic challenger may have multiple positions, careful vetting and strategic fact discovery will focus on information that supports its defenses while avoiding downsides.

Recent cases demonstrate that inventor testimony can damage an obviousness challenge. Before retiring, Chief Judge Gregory M. Sleet of the District of Delaware found inventor testimony compelling when rejecting a generic company’s obviousness challenge, in Pfizer Inc. v. Mylan Pharmaceuticals Inc.,[10] stating:

Finally, the process engaged by the inventors’ [sic] demonstrates the highly unpredictable nature of the prodrug development research. … The inventor’s results, and Dr. Janero’s ultimate admission that prodrugs are complicated, are powerful evidence of the unpredictability inherent in prodrug design, a factor that weighs strongly against an obviousness finding.

The Pfizer decision had multiple components, including rejection of the lead compound and arguments for modifying it to arrive at the claimed structure.[11] Nevertheless, Judge Sleet’s comments concerning the inventors are arresting.

In another recent case, Bayer Intellectual Property GmbH v Aurobindo Ltd.,[12] the court rejected defendants’ obviousness arguments, citing among other things, inventor testimony:

I find even stronger support for the non-obviousness of claim 16 of the ’456 patent in the struggles of the inventors to arrive at rivaroxaban. The plaintiffs describe the fortuitous path the inventors took to arrive at rivaroxaban … [describing high-throughput screening, dead end leads, many compounds prepared] … I find that this evidence provides further proof that claim 16 of the ’456 patent is non-obvious.

Here there were several factors involved, including the lead compound and arguments for modifying it.[13] But again, the inventors’ testimony was impactful on the fact-finder. To be sure, inventor testimony was not the sole reason for these unsuccessful obviousness defenses.[14] It is clear, however, that inventor testimony did nothing to help the generic defendants but it does appear to have significantly helped the patentee/innovator side.

The convention of seeking inventor testimony muddles the generic defendant’s case further because obviousness arguments frequently come down to a battle of expert witnesses. Experts will define the scope and content of the prior art,[15] the level of ordinary skill in the art,[16] and compare the prior art to the claims at issue.[17] An inventor can provide no facts to inform any of the prongs of the obviousness standard. Therefore, a named inventor’s testimony cannot be used to establish the prima facie obviousness case.

The secondary considerations of nonobviousness analysis typically relies on expert testimony based on facts rarely exclusive to the named inventors. One can easily envision the generic defendant coming forward with evidence supporting secondary considerations without involving an inventor at all.

Cost is another important reason to carefully consider whether to take inventor depositions. Meaningfully preparing for, traveling to, and conducting inventor depositions represents a time-consuming, costly proposition that generic defendants might more efficiently focus elsewhere in their case.

That is not to say that inventor testimony is never useful. The patent challenger’s defenses may include such a component or it may learn through discovery that there is a discrete role for inventor testimony. Inventor depositions can then be taken where appropriate.

The innovator side will likely be eager to inject inventor testimony into the case for many reasons. Notably, a lay federal judge listening to an erudite scientist storytelling from the stand can create a formidable foundation for the patentee/innovator’s nonobviousness case. Therefore, the savvy generic defendant relying on an obviousness defense should set up its case to minimize — or prevent, if possible — inventor involvement and pursue fact evidence from other sources. While ultimately the generic filer may not be completely able to restrict the presence of inventor testimony, opening a door to it is probably not the best choice.

A perceived downside to not taking inventors’ depositions is the risk of them testifying at trial with no prior vetting; this is not insurmountable. In a generic drug case, the parties often stipulate to infringement converting the case to one about patent validity. In fact, the generic defendant often understands that stipulation is inevitable; the real issue is when. Because of this case repositioning, the generic defendant stands essentially in the shoes of a declaratory judgment plaintiff and, therefore, should strive to put on its case first. From this realignment the generic defendant should have more control over the order of witnesses at trial and seek to preclude inventor testimony completely, or at least limit tales of the invention story.[18]

Another potential pitfall exists where the patentee/innovator includes the named inventors in their Rule 26 disclosures, anticipating to elicit their testimony at trial. But in a obviousness case, what can an inventor really add? The statue, the Supreme Court’s KSR ruling, and the Federal Circuit’s Otsuka Pharmaceutical Co. v. Sandoz Inc. decision all suggest that the inventor’s testimony is irrelevant to the question of obviousness. Surely the patentee/innovator will argue that the inventor needs to explain to the fact finder topics like the background of the invention, or the technology. But neither of these things form part of the obviousness inquiry and the parties experts will surely testify — at length — about the relevant technological background in any event.[19]

Undoubtedly there will exist cases where the invention story forms an important component of a patent validity challenge and inventor testimony necessary. Savvy generic defendants should make such determinations early, rather than following convention and hoping for the best. The generic defendant who haphazardly deposes inventors, creates an unfavorable record, and ensures the inventor’s appearance at trial — unwittingly gives away the game before it really starts. Perhaps generic challengers will instead pursue different routes to obtain evidence in support of their obviousness cases, and, as a result, avoid acting like the archetypal lemming that follows the crowd — who then plunges over the cliff’s edge.

Disclosure: The author and his colleagues represented one of the generic defendants in the Bayer Intellectual Property GmbH v. Aurobindo Pharma Ltd. case, referenced herein.

The opinions expressed are those of the author(s) and do not necessarily reflect the views of the firm, its clients, or Portfolio Media Inc., or any of its or their respective affiliates. This article is for general information purposes and is not intended to be and should not be taken as legal advice.

[1] The Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 301 et seq.

[2] There are two well-known exceptions: first, a prior art disclosure more than one year before the filing date of the application for patent under scrutiny, and second, a prior patent or publication by one inventor that is also a joint inventor on later filed application. 2 CHISUM ON PATENTS § 503[3][f](citing cases). These exceptions are not relevant to this commentary.

[3] Analytics platform Lex Machina in its Hatch-Waxman ANDA Litigation Report 2018, for the years 2016 and 2017, compiled “ANDA Patent Invalidity Reasons by Judgment” for reported case terminating events. ( (subscription required).) Under the Lex Machina rubric, these events include: default, consent and summary judgments; judgment on the pleadings; judgment as a matter of law; and trial. The reasons cited in the report include: obviousness (15 cases), section 112 (10, split between best mode, enablement, and definiteness), patentable subject matter (3), and novelty (3) along with some others.

[4] Graham v John Deere Co. of Kansas City , 383 U.S. 1, 17-18, 86 S.Ct. 684 (1966).

[5] Id.

[6] Id. at 17; Bristol-Myers Squibb Co. v. Teva Pharms. USA, Inc. , 769 F.3d 1339, 1341 (2014).

[7] 35 U.S.C. § 103.

[8] Otsuka Pharm. Co. v. Sandoz Inc. , 678 F.3d 1280, 1296 (Fed. Cir. 2012).

[9] KSR Intern. Co. v. Teleflex Inc. , 550 U.S. 398, 419-420, 127 S.Ct. 1727, 1741-1742 (2007).

[10] Pfizer Inc. v. Mylan Pharms. Inc. , 2017 U.S. Dist. LEXIS 125634, *39-40 (D. Del. Aug. 9, 2017).

[11] Id. at 26-32, 32-39.

[12] Bayer Intellectual Prop. GmbH v. Aurobindo Pharma Ltd. , 2018 US. Dist. LEXIS 116931 *39, n. 20 (D. Del. July 13, 2018) (E.D. Pa. Judge Lawrence F. Stengel (retired) sitting by designation).

[13] Id. at 16-24, 25-33.

[14] These were both complex cases where the Court in both instances also found plaintiffs’ experts more credible on certain issues.

[15] See Liposome Co. v. Vestar, Inc. , 36 U.S.P.Q.2d 1295, 1313 (D. Del. Dec. 20, 1994) (“Thus, the scope and content of the prior art includes references from those areas a person with ordinary skill in the art would look to in solving a particular problem.”).

[16] Biacore, AB v. Thermo Bioanalysis Corp. , 79 F. Supp. 2d 422, 464 n.46 (D. Del. 1999) aff’d, 30 Fed. Appx. 994 (Fed. Cir. 2002) (“There are six factors a court should consider in determining the level of ordinary skill in the art: (1) the educational level of the inventor; (2) the type of problems encountered in the art; (3) the prior art solutions; (4) the rapidity of innovation; (5) the sophistication of the technology at issue; and (6) the educational level of active workers in the field”.).

[17] This prong is a question of law for the court. Graham, 383 U.S. at 18 (“While the ultimate question of patent validity of one of the law, [citation omitted] the § 103 condition, with is but one of three conditions, each of which must be satisfied, lends itself to several basic factual inquiries.”).

[18] Another effective approach involves the parties agreeing in advance that the generic defendant will not depose the inventors if the patentee/innovator will not bring them to trial.

[19] It is a near certainty that the parties pretrial briefs, as well as their previous Markman briefs, will explain in detail the relevant technological background so the trier of fact will have heard the technical background multiple times. Therefore, motions in limine provide an alternate way to preclude or limit inventor testimony.


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