Here's a scenario that can happen in a patent case: The patentee serves an opening expert report alleging infringement. Your expert responds, detailing every reason why the design documents show non-infringment. The patentee then serves a reply expert report, citing new documents that it says show infringement.
What do you do now? There are at least four answers: (1) move for leave to serve a sur-reply report to address the new docs; (2) just serve a sur-reply report, without leave, and fight the inevitable motion to strike; (3) skip the report but have the expert be prepared to discuss the new papers at deposition, and hope plaintiff asks; or (4) just plan to address the new arguments at trial.
Each of those strategies has their disadvantages. In Oasis Tooling, Inc. v. GlobalFoundries U.S., Inc., C.A. No. 22-312-CJB (D. Del. June 6, 2024), the defendant apparently chose "serve a sur-reply and fight the motion to strike." It did not go well for them:
ORAL ORDER: The Court, having reviewed Plaintiff’s motion to strike certain portions of Defendant’s supplemental rebuttal expert reports on non-infringement . . . , hereby ORDERS that the Motion is GRANTED and that the paragraphs are STRICKEN, for the reasons that follow: (1) The Scheduling Order provided that after reply expert reports were filed, “[n]o other expert reports will be permitted without either the consent of all parties or leave of the Court[.]” . . . The one listed exception was that if the Court issued a claim construction decision after the service of either rebuttal or reply expert reports (which happened here), then an expert could submit a “supplemental report[]... that [is] limited to reasonable supplementation in view of the claim construction order.” . . . (2) In its briefing, Defendant makes no real attempt to argue that the paragraphs at issue were crafted “in view of the claim construction order”—with the exception of one (too vague) assertion about one such paragraph. . . . And the Court, having reviewed the paragraphs at issue, cannot see how they engage with the substance of the Court’s claim construction order in any explicit way. . . . So the submission of the paragraphs at issue violate the text of the Scheduling Order, meaning that Defendant must show good cause in order that they be permitted.
The Court found no good cause—and included some useful quotes:
(3) Defendant did not show good cause here. Instead, it suggested that the paragraphs at issue should be permitted because they address documents that Plaintiff’s infringement expert mentioned for the first time in his reply report. (D.I. 341 at 3) But so long as a reply report is properly responding to the substance of a rebuttal report, there is no bar on an expert relying on a document for the first time in that reply report. And Defendant did not otherwise show how the substance of Plaintiff’s expert’s reply report was improper reply material. Cf. Azurity Pharms., Inc. v. Alkem Lab’ys Ltd., Civil Action No. 19-2100-MSG, D.I. 178 (D. Del. July 11, 2022) (permitting a supplemental expert report, but where it was in response to arguably untimely material included in the other side’s reply expert report on the subject). There is nothing diligent on Defendant’s part about submitting a new sur-reply expert report when one is not permitted by the Scheduling Order. And permitting that could cause prejudice to a party in Plaintiff’s shoes, especially if (as was suggested by Defendant here), (D.I. 341 at 1, 4), such a plaintiff would have to go to the time and expense of having its expert file yet another supplemental report in response. . . . The whole point here is that the reason why parties agree to Scheduling Order limits on expert reports (like the parties did here) is because at some point, the submission of expert reports has to end.
There are a couple of notable points here:
- Experts can rely on a document for the first time in a reply report.
- It's not "diligent" to submit an impermissible sur-reply report
- "[A]t some point, the submission of expert reports has to end."
- The fact that the opposing party will have to serve a sur-reply will cause prejudice to them.
The last point in particular is interesting. When applying the Pennypack factors, the Court looks at the opposing party's "ability to cure" the prejudice to itself. Sometimes, the Court has denied relief, holding that an opposing party can "cure" the prejudice by serving a sur-reply report. See, e.g., Zimmer Surgical, Inc. v. Stryker Corp., 365 F. Supp. 3d 466 (D. Del. 2019) (denying motion to exclude where "any prejudice . . . may be cured by permitting [the moving party] to file a sur-reply report").
If the act of having to draft and serve a sur-reply report is itself prejudicial, then it seems obvious that serving a surreply cannot "cure" prejudice (or at least not all prejudice). This will be a handy cite!
Option 4: "We'll Do It Live!"
Interestingly, the Court went on to suggest that, even though it struck the expert's report, the expert could still testify about the opposing expert's new documents:
All of the above said, this doesn’t necessarily mean that Defendant’s experts won’t be able to discuss their views at trial (assuming there is a trial) regarding documents that Plaintiff’s expert cited for the first time in reply. So long as Defendant’s experts’ opinions in this regard are fairly within the bounds of the arguments/theories those experts espoused in their rebuttal opinions regarding non-infringement, then they can be stated. Put another way, if one side’s expert references a document for the first time in a reply report (as part of a legitimate and proper reply argument), there is no per se rule that says that the other side’s expert is forbidden from ever having or expressing a view at trial regarding what that document is or says or means.
This, too, is a great holding to keep in your back pocket for trial!
That said, it works here because it came from the judge who is going to be trying the case. If you were a litigant before another judge, without such an explicit opinion on this issue, would you trust that the Court would permit your expert to testify outside of the literal bounds of his report?
In practice, at trial, the expert will be on the stand testifying, and opposing counsel will make an outside-the-scope objection. At that point you have a few seconds (often at sidebar) to find where in the expert's report they discussed whatever it is they are testifying about. Any judge may run out of patience quickly with that kind of discussion, and if you get into "well, your honor, the opposing expert cited these documents in their reply..." you are at risk of a quick ruling against you.
Even if you ultimately prevail, you are going to be burning your trial time arguing about whether the Court should permit the expert to offer this testimony, and potentially losing the jury's interest while they naturally zone out during a side bar.
So, absent an opinion like the above in your case, it may still be a tough judgment call on how to handle responding to new arguments like this in a reply report.
If you enjoyed this post, consider subscribing to receive free e-mail updates about new posts.