A Blog About Intellectual Property Litigation and the District of Delaware


Entries for tag: Claim Narrowing

Claim narrowing is such a common issue in Delaware that this blog has at least 431 entries with the tag.

(Eds. Note—I did not actually count, but you can click on the tag on the side and scroll down to prove me wrong).

I told it to draw a nerd, but it actually kind of looks like me...must be something wrong with the algorithm.
I told it to draw a nerd, but it actually kind of looks like me...must be something wrong with the algorithm. AI-Generated, displayed with permission

Ironically this rich well of precedent can make it kind of hard to brief a dispute on claim narrowing. A dozen cases can be cited for any proposition you might want, which can make it hard to argue for one outcome over another -- especially to a judge that has seen similar disputes so many times before.

Judge McCalla's opinion last week in Aortic Innovations, LLC v. Edwards Lifesciences Corp., C.A. No. 23-158-JPM (D. Del. Mar. 20, 2025), was thus a breath of fresh air as he writes unencumbered by a wealth of his own words on the issue.

In the opinion (which cites to a truly remarkable number of prior Delaware orders on the issue), he dealt with 3 relatively common questions in the district.

First, the parties disputed whether the plaintiff should narrow from 31 asserted claims down to 18 or 15 (I'll let you guess who was proposing which). Judge McCalla went with 18, citing Judge Fallon's Order in Twinstrand Bioscis., Inc. v. Guardant Health, C.A. No. 21-1126-GBW-SRF (D. Del. Oct. 18, 2022), which stated that “a reduction to approximately 20 claims by the deadline for service of final infringement contentions” is “consistent with other case narrowing order[s] from [the District of Delaware].”

Next the parties ...

Plaintiffs in the patent game tend to treat prior art references like particular unwelcome guests. There is an obvious level of affront when they arrive, tempered only by what politeness can be mustered. Once they are in the door, there are constant references to how crowded it is, how little air, how maybe we should just call it a night even though its just so much fun to see everyone.

(Eds. Note -- can you tell I'm from the midwest? I was going over this metaphor with one of the many New Yorker's I know and they seemed not to get the dynamic).

Once you finally cajole them our of the house, packed with leftovers and other bribes, it …

AI-generated depiction of Judge Andrews putting down zombie claims for good.
AI-generated depiction of Judge Andrews putting down zombie claims for good. AI-Generated, displayed with permission

Former Chief Judge Sleet used to frequently say that "there is no such thing as the law of the district." Genentech, Inc. v. Amgen Inc., No. 17-1407-GMS, 2018 U.S. Dist. LEXIS 9544, at *8 n.3 (D. Del. Jan. 22, 2018) (cleaned up). In other words, one district court judge's ruling is not binding on another.

We saw that yesterday, when Judge Andrews held that claims dropped due to claim narrowing are dropped with prejudice, and recognized that another of our judges had previously held the opposite on similar facts.

In Exeltis USA, Inc. v. Lupin Ltd., C.A. No. 22-434-RGA (D. …

Disappointment Ice Cream
Sarah Kilian, Unsplash

In Exeltis USA, Inc. v. Lupin Ltd., C.A. No. 22-434-RGA-SRF (D. Del.), plaintiff asserted infringement of claims from six patents. Back in July, 2023, Judge Andrews ordered the plaintiff to narrow its case to seven asserted claims across all of the patents prior to trial, which is set for Monday, February 26, 2024.

On Tuesday of this week, the Court issued its ruling on several pre-trial claim construction disputes. Plaintiff lost some of the disputes and, apparently, decided that it needed to stipulate to non-infringement of that claim.

With one of its seven claims out of the case, and with less than a week to go before trial, Plaintiff sought leave to re-assert one …

Abacus
Sami, CC BY 2.0

There was an interesting oral order from Judge Burke last week in Natera, Inc. v. CareDX, Inc., C.A. No. 20-38 (D. Del. Apr. 28, 2023). Defendant apparently asserted a large number of § 112 defenses based on lack of enablement or written description. The Court held that the defendant had to narrow it's defenses.

The parties further disputed whether the parties should count § 112 arguments by limitation or by claim. The Court held that they should be counted by claim limitation, not by claim:

With respect to the parties' dispute as to whether an argument that a claim is invalid under section 112 based on a particular claim limitation counts …

I usually don't expect a fight about withdrawing a claim. Adding one? sure. Striking one? Also Sure. Squishing two of them together and pretending they're dancing? Definitely.

Go Ninja, Go Ninja, Go!
Go Ninja, Go Ninja, Go! AI-Generated, displayed with permission

Generally though, the voluntary withdrawal of a claim makes life easier for the parties and the Court and passes from the case without comment or concern. That said, you can see why the withdrawal in MirTech, Inc. v. AgroFresh, Inc, C.A. No. 20-1170-RGA (D. Del. Mar. 23, 2023) (Mem. Op.) was more contentious.

The case had been pending for almost two years when Judge Andrews "encouraged the parties to avoid the over-litigation that [he] thought was happening in th[e] case." This "encouragement" took place about a week before the Defendant moved for SJ on several topics. plaintiff filed its opposition brief a month after that.

The defendant then took the unusual step of withdrawing one of the claims it had moved on—nominally without ...

This morning I woke up and everything hurt. It was cold, and my old house made a sound like a sad kazoo with every mournful gust of wind. I'm still working out the physics of that last bit. As I sat down to my porridge, I admitted to myself that I was old.

More than usually cursed art (FYI, it's supposed to be a kazoo)
AI-Generated, displayed with permission

Anyway.

All this is to say that I felt like nothing was going my way. So I empathized with the filers of a seemingly simple stipulation in Cleveland Medical Devices, Inc. v. ResMed Inc., C.A. No. 22-794-GBW.

The scheduling order there differed from Judge Williams' form in that it added a specific provision for the reduction of prior art, limiting the number of claims asserted for each patent, as well as the number of prior art references for each patent:

The parties shall reduce the number of asserted claims and asserted prior art used for anticipation and obviousness combinations as follows:
• On January 9, 2023 . . . Plaintiff shall serve an Initial Election of Asserted Claims, which shall identify no more than 64 total asserted claims, and no more than 10 asserted claims per patent.
• On February 8,2023 . . ., Defendant shall serve an Initial Election of Prior Art, which shall identify no more than 64 total references and no more than 10 references per patent that can be used for anticipation or as combinations for obviousness . . .

Id. at D.I. 41 Paragraph 3(g).

Later, the parties had a dispute over the per-patent cap ...

Crissy Jarvis, Unsplash

An interesting opinion from Judge Thynge last week on case narrowing, and in particular, how to count invalidity arguments.

The defendant in Targus International LLC v. Victorinox Swiss Army, Inc.., C.A. No.20-464-RGA-MPT (D. Del. Nov. 18, 2022), had agreed to reduce the number of prior art "arguments" to 5. In its expert reports, however, they had counted reference "A in view of B", as well as "B in view of A" as a single argument. This lead to the inclusion of (what plaintiff counted as) more than 5 arguments. Plaintiff then moved to strike the extraneous arguments and Judge Thynge agreed, holding:

In its letter brief, Defendant maintains that it "never labeled any reference …

"Do you think 11 patents might be more than we need? Nah" Maciej Ruminkiewicz, Unsplash

Back in May, we wrote about an order by Chief Judge Connolly directing an ANDA plaintiff to cut back to 4 claims prior to trial, or potentially face a more difficult road for injunctive relief.

Plaintiff cut back to 6 claims, apparently dropping five patents from the case, and the bench trial proceeded.

Last month, Chief Judge Connolly issued his post-trial opinion regarding infringement and invalidity, and directed the parties to enter a proposed order. The parties ended up disputing what should happen to those dropped claims from the five dropped patents in the final judgment:

The proposals differ with respect to the disposition …

Drop
Andrew E. Russell, CC BY 2.0

In my experience, parties in patent actions in the District of Delaware (and elsewhere) routinely drop claims in the lead up to trial. "Dropping claims" includes withdrawing asserted claims (e.g. "Claim 1"), whole asserted patents (e.g., "the '123 patent"), infringement contentions (e.g., "direct infringement" or "infringement by product A"), and other claims (including non-patent claims).

Most often, in practice, this is accomplished via an e-mail to the other side or, if the parties want something on the docket, by stipulation. I don't know of a case where the Court here insisted that a plaintiff not drop claims (of course, a defendant may also have counterclaims).

Are the Claims Withdrawn with Prejudice?

But parties rarely …