The District of Delaware local rules prohibit additional briefing on motions beyond the opening, answering, and reply briefs permitted by the rules, and the "citation of subsequent authorities":
Except for the citation of subsequent authorities, no additional papers [beyond the response to a motion and a reply brief] shall be filed absent Court approval.
D. Del. Local Rule 7.1.2(b).
It's clear that the "citation" of subsequent authorities is permitted, but what about substantive argument regarding those new authorities?
The Court has sometimes permitted substantive argument in notices of subsequent authority, and such notices can prove highly effective. Other times, it has declined to consider improper notices of subsequent authority or struck argumentative responses thereto. See EIS, Inc. v. Intihealth Ger GmbH, No. 19-1227-GBW, 2023 U.S. Dist. LEXIS 102433, at *4 n.1 (D. Del. June 13, 2023) (declining to consider improper notice of subsequent authority).
Last week, Judge Fallon responded to a series of argumentative notices of subsequent authority, and responses, by directing the parties to stop filing them. She also clarified that notices of subsequent authority should be limited to a "non-argumentative" cover letter, and that no response is permitted:
ORAL ORDER- re 41 Letter. IT IS ORDERED that no further letter briefing on the motion to dismiss (D.I. 23) will be permitted absent leave of court. District of Delaware Local Rule 7.1.2(b) allows a party to file a notice of subsequent authority. D. Del. LR 7.1.2(b). Such notices should be limited to a non-argumentative cover letter with the subsequent authority attached as an exhibit. Rule 7.1.2(b) does not contemplate the filing of a "response" to a notice of subsequent authority. See Targus Intl LLC v. Victorinox Swiss Army, Inc., C.A. No. 20-464-RGA, 2020 WL 7264199, at *1 n.2 (D. Del. Dec. 10, 2020). The court has the pending fully briefed motion to dismiss under advisement, and the filing of additional argumentative letter briefs does not advance the timely resolution of the motion. The court will issue a Report and Recommendation in due course. Ordered by Judge Sherry R. Fallon on 12/11/2025. (lih) (Entered: 12/11/2025)
Safety Holdings Inc. v. Sentinel Information Systems LLC, C.A. No. 24-1224-RGA, D.I. 42 (D. Del. Dec. 11, 2025).
While the Court did not strike the improper notices, its opinion, issued just five days later, did not reference them. Id., D.I. 43.
If you enjoyed this post, consider subscribing to receive free e-mail updates about new posts.
