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 …
