Why Patent Reexaminations Are Experiencing a Resurgence

Why It Matters

The trend gives litigants a predictable, cost‑effective alternative to IPR, reshaping post‑grant strategy and influencing law‑firm positioning.

Key Takeaways

• PTAB IPR institution rates falling, prompting shift to reexamination
• Reexamination costs a fraction of IPR, often under $100k
• No estoppel from ex parte reexamination preserves later court defenses
• Requests can be filed anytime during a patent’s enforceable life
• Faster resolution and higher claim‑amendment rates boost strategic value

Pulse Analysis

Since the America Invents Act introduced inter‑partes review (IPR) and post‑grant review (PGR), PTAB proceedings have dominated U.S. post‑grant practice. However, recent policy shifts and a surge in discretionary institution denials have eroded the predictability that challengers once relied on. Data from the USPTO shows a sharp rise in procedural rejections of IPR petitions, even as overall patent litigation volumes climb. This environment has left litigants searching for a more reliable mechanism to test patent validity without the procedural hurdles now common at the PTAB.

Ex parte reexamination offers a contrasting path that sidesteps many of those hurdles. The proceeding is triggered by a “substantial new question of patentability,” a lower threshold than the IPR petition standard, resulting in institution rates that consistently exceed those of PTAB reviews. Costs are markedly lower—often under $100,000 compared with the six‑figure expenses typical of IPRs—and the process lacks discovery, depositions, or oral arguments, accelerating timelines. Crucially, reexamination does not impose statutory estoppel, allowing challengers to preserve any invalidity arguments for later district‑court litigation.

The resurgence of reexamination reshapes how law firms advise clients. Firms with strong prosecution benches can navigate the examiner‑driven process, crafting persuasive arguments that maximize claim amendments or cancellations. Simultaneously, litigation‑focused practices must evaluate whether an IPR, a reexamination, or a coordinated dual strategy best serves the client’s broader case. As the USPTO continues to refine the Central Reexamination Unit’s workflow and as courts increasingly stay cases pending reexamination, the procedure is cementing its role as a core component of modern patent‑defense arsenals. Expect continued growth as cost pressures and PTAB uncertainty persist.