Medpace, Inc. v. Agenus Inc.

Background

Medpace, Inc. sued Agenus Inc. and Equiniti Trust Company, LLC. The complaint invoked diversity jurisdiction under 28 U.S.C. § 1332. Diversity jurisdiction is a basis for federal-court authority that generally requires complete diversity of citizenship between the opposing parties.

Medpace alleged that it was a citizen of Ohio and that Agenus was a citizen of Delaware and Massachusetts. For Equiniti, however, Medpace alleged only, on information and belief, that it was a New York limited liability company with Delaware and/or New York members.

Court’s Analysis

The court explained that a limited liability company is considered a citizen of every state where its members are citizens. A complaint relying on diversity jurisdiction therefore must identify the citizenship of each LLC member. If a member is an individual, the complaint must allege that person’s citizenship. If a member is a corporation or another LLC, the complaint must provide the required citizenship information for that entity and, when applicable, trace the citizenship through additional LLC members. The court also stated that citizenship must be affirmatively pleaded rather than alleged only in conclusory terms.

The court concluded that Medpace’s complaint did not affirmatively plead the citizenship of each member of Equiniti.

Order

The court ordered Medpace to amend its complaint by May 28, 2025. The amended complaint must affirmatively allege the citizenship of each person or entity comprising Equiniti and the citizenship of all individual parties. If Medpace cannot truthfully allege complete diversity of citizenship, the court stated that the complaint will be dismissed for lack of subject matter jurisdiction without further notice. The order did not decide the merits of the underlying dispute.