1. Home
  2. |Insights
  3. |D.C. Circuit Creates Split over the Reach of the First-to-File Bar

D.C. Circuit Creates Split over the Reach of the First-to-File Bar

Client Alert | 1 min read | 04.18.14

In U.S. ex rel. Shea v. Verizon Co., the D.C. Circuit held that (1) two complaints may be "related" even if they involve different agencies or contracts, (2) the bar applies even when the same relator filed the earlier action, and (3) it continues to operate even after the earlier-filed action is resolved. The third holding (which drew a dissent) conflicts with dicta from two other circuits and the Fourth Circuit's 2013 opinion in U.S. ex rel. Carter v. Halliburton Co., petition for cert. filed (discussed here), holding that the first-to-file bar only applies while the earlier action is still pending.

Insights

Client Alert | 3 min read | 05.26.26

pH, Prosecution History Estoppel, and Patent Scope: Three Lessons from the Federal Circuit's Latest Hatch-Waxman Ruling

On May 13, 2026, the U.S. Court of Appeals for the Federal Circuit affirmed a district court judgment of no infringement in Actelion Pharmaceuticals Ltd. v. Mylan Pharmaceuticals Inc., No. 24-1641. The decision offers important guidance for patent holders and generic manufacturers on the role of industry standards in interpreting scientific terminology during claim construction, prosecution history estoppel, and the disclosure-dedication rule....