The three New York partners are E. Joshua Rosenkranz, former head of Heller's appellate practice; Richard Goldstein, an antitrust partner; and Edward Joyce, an insurance recovery partner.
The rest of the partners were spread among San Francisco, Washington, D.C., London and Seattle. They include eight of Heller's former practice leaders, as well as three former firmwide chairmen.
Orrick Chairman Ralph Baxter hailed the additions Thursday, pointing to the "critical mass" of antitrust lawyers joining the firm.
Half of the former Heller partners will join Orrick in antitrust, including former competition group head Stephen Bomse and trade regulation head Robert Rosenfeld, both in San Francisco.
Baxter also said Rosenkranz brought to Orrick a "destination" U.S. Supreme Court practice. Rosenkranz was founding president of the Brennan Center for Justice at New York University School of Law before joining Heller in 2003.
Other firms, including Covington & Burling, Arnold & Porter and Pillsbury Winthrop Shaw Pittman, also have announced Heller hires in recent days, though mostly on the West Coast.
Heller's most sought-after New York partner, high-profile securities litigator Lawrence J. Zweifach, has notably yet to announce a move. He did not return a call seeking comment.