Lam Research v. Inpria: Voluntary Dismissal in EUV Photoresist Patent Dispute

Case Overview

The Parties

Patents at Issue

This case centered on **US Patent No. 9,823,564 B2** (Application No. US14/858612), which claims inventions directed to patterned inorganic layers, radiation-based patterning compositions, and corresponding methods. This patent covers material compositions and patterning methodologies directly relevant to EUV photolithography, a critical manufacturing step in cutting-edge chips.

• • US 9,823,564 B2 — Patterned inorganic layers and radiation-based patterning compositions.

The Verdict & Legal Analysis

Outcome

The Federal Circuit dismissed Case No. 25-1872 pursuant to **Fed. R. App. P. 42(b)** — a voluntary dismissal mechanism — on September 17, 2025. No damages were awarded by the court. No injunctive relief was granted or denied on the merits. Each party was ordered to bear its own costs, a standard provision in consensual dismissals that signals neither side extracted a fee-shifting concession.

Because the dismissal is voluntary and the underlying patentability dispute was not adjudicated on the merits, **no binding Federal Circuit precedent was established** in this proceeding.

Key Legal Issues

The case was designated as an **Invalidity/Cancellation Action**, placing the core legal dispute squarely on whether US9823564B2 constitutes valid, enforceable IP. Patent validity challenges at the Federal Circuit typically arise after a PTAB decision in IPR or post-grant review (PGR) proceedings.

Without a merits ruling, the precise arguments that drove the appeal — and ultimately the settlement — remain confidential. However, the involvement of both Morgan Lewis and Paul Hastings, firms with deep PTAB and Federal Circuit experience, suggests the validity arguments were substantively developed before the dismissal occurred.