Sterne Kessler Goldstein & Fox P.L.L.C is the first patent law firm to represent petitioners or patent owners in at least 500 patent challenges before the Patent Trial and Appeal Board established under the America Invents Act of 2012, according to information from Docket Navigator.

Washington, D.C.-based Sterne Kessler’s PTAB practice, which is led by partners Rob Sterne, Eldora Ellison, Lori Gordon, and Jon Wright, has represented petitioners on 208 cases and patent owners in 292 cases. The cases include 448 inter partes reviews (IPRs), 45 covered business method (CBMs) reviews, 3 derivation proceedings (DERs) and 4 post grant reviews (PGRs).

“Our continued success at the PTAB follows directly from our technical depth and nearly 40 years of patent prosecution experience for some of the most innovative companies in the world,” Sterne said in a statement. “We are able to leverage these advantages to consistently achieve success for patent owners and for petitioners across a broad range of technologies.”

Sterne, alone, has handled over 120 AIA proceedings since the PTAB was established. The law firm is closely followed in the rankings by Fish and Richardson with 485 cases and

Finnegan with 473.

Fish and Richardson have handled the most petitions to the PTAB with 300, followed by Finnegan with 250, Sterne Kessler with 208 and Wilmer Hale with 202.

Finnegan is ranked No. 2 behind Sterne Kessler in its defense work with 223 cases, followed by Fish and Richardson at No. 3 with 185.

Officials from Fish and Richardson and Finnegan couldn’t be reached for comment.