New York attorney · Reg. #4244711

William Joseph O'Brien

Registered (registry: Currently registered)

Current employer

O'Brien Firm PC · Philadelphia, PA · since at least September 2026

Admission

Admitted 2004, Third Department · CATHOLIC UNIVERSITY

Employment history

• O'Brien Firm PC · Philadelphia, PA · current

Compiled from NYS Office of Court Administration registration records and published NY Appellate Division decisions; current as of October 2026. Not an official record; verify with the NY Courts Attorney Search.