Ex Parte Reexam Requests Remain Near Their Peak Amid Ongoing NHK-Fintiv Uncertainty

The Patent Trial and Appeal Board’s (PTAB’s) practice of discretionarily denying inter partes review (IPR) petitions due to the status of parallel litigation, known as the NHK-Fintiv rule, has long been a source of uncertainty for patent infringement defendants. This uncertainty has continued to push defendants toward ex parte reexaminations, which are not subject to such denials to the same extent as America Invents Act (AIA) reviews. Ex parte reexam filings first began to rise three years ago in response to growing concern over NHK-Fintiv: The number of such requests went up by 21% in 2020 and then by 53% in 2021, peaking that year.

Since then, yearly reexam filings have held steady, hovering around 330 requests for each of the past two years—with 2023 the second-highest filing year of the past decade. If Q1 2024 is any indication, this could be an even busier year: 89 reexam requests were filed in the first quarter, or 37% more than in Q1 2023.

The share of patents subject to reexam requests that were also previously challenged at the PTAB has fallen each year, from 36% in 2021 to 24% in 2023, and reaching just 18% in the first quarter of 2024. Meanwhile, the share of those reexam patents also litigated in district court has held steady. Together, this suggests that defendants have been placing less emphasis on the PTAB as uncertainty over discretionary denials persists and that reexams have kept their spot as a more frequently utilized defensive tool.

See RPX’s first-quarter review for more on the PTAB and other key patent litigation trends from Q1 2024.