Roberta Kaplan, the prominent New York attorney who successfully argued before the U.S. Supreme Court to overturn the Defense of Marriage Act, has left Paul, Weiss, Rifkind, Wharton & Garrison to form a litigation boutique.

Her new firm, Kaplan and Co. LLP, includes four lawyers for now, including partner Julie Fink, previously in-house counsel at Pfizer Inc. and a Paul Weiss attorney; senior counsel John Quinn, a former litigation associate of Sullivan & Cromwell; and associate Rachel Tuchman, a recent Yale Law School graduate. It will have offices in Manhattan’s Empire State Building.