What happened

On October 1, 2026, the Federal Circuit affirmed a District of Delaware judgment holding claims 1, 11, and 18 of U.S. Patent 6,711,385 invalid. Chief Judge Moore wrote the precedential opinion in Satius Holding, LLC v. Samsung Electronics Co., Ltd., No. 2025-1446, for a panel with Judges Lourie and Hughes. The court agreed with Satius that the indefiniteness ruling was erroneous, but affirmed on enablement under 35 U.S.C. 112(a), as Samsung urged.

The district court's ruling

Satius sued Samsung in 2018 for allegedly infringing the three claims. After a stay pending reexamination, the district court (Magistrate Judge Christopher J. Burke, No. 1:18-cv-00850-CJB) held the claims indefinite in a December 12, 2024 decision and entered final judgment of invalidity for Samsung. Claim 1 recites "[a] communications apparatus for transmitting electric or electromagnetic signals over air." Per the Federal Circuit, the district court reasoned that "it is an undisputed scientific impossibility to transmit electric signals over air."

Indefiniteness is not impossibility

The panel construed "transmitting electric . . . signals over air" to mean transmitting signals over air in electric form, which neither party disputed is scientifically impossible. It rejected Satius' reading that the phrase refers to an electric signal transformed inside the device into an electromagnetic one: "Transmitting signals over the air is not the same as transmitting signals to the air." Quoting Chef America, Inc. v. Lamb-Weston, Inc., it said it "may not redraft claims . . . to make them operable or to sustain their validity."

The core holding: "Indefiniteness is not the same as impossibility." The court wrote that while a claim may be "so nonsensical that a skilled artisan would struggle to understand the bounds of the claim, there is no per se rule that a claim covering inoperable embodiments is necessarily indefinite." These claims, the court held, "encompass inoperable embodiments" but "are clear about what they cover," which satisfies Nautilus, Inc. v. Biosig Instruments, Inc.

The panel distinguished Synchronoss Technologies, Inc. v. Dropbox, Inc., 987 F.3d 1358 (Fed. Cir. 2021), which held indefinite claims that "require[d] an impossibility." Those claims were also "nonsensical," and the specification showed a skilled artisan they did not set forth what the inventor regarded as the invention. Here, the impossible language appears in both the claims and the written description, and Samsung argued that claim 1 "unmistakably claims" the impossibility. A footnote calls the Samsung expert testimony the district court quoted "conclusory extrinsic evidence" and rejects the district court's per se impossibility rationale: "There is no such per se rule."

Enablement, decided on appeal

The district court said it "struggle[d] to see how the full scope of claim 1 could be enabled," but treated enablement as waived. The Federal Circuit saw "no bar" to reaching the issue, citing Singleton v. Wulff: the parties briefed it, enablement is a question of law, the impossibility was undisputed, and non-enablement was "so evident" that a remand "would serve no purpose."

The court applied Amgen Inc. v. Sanofi: "the specification must enable the full scope of the invention as defined by its claims." That standard "cannot possibly be met," it held, when claims "include an express limitation that adds inoperable (and thus non-enabled) alternative embodiments to the scope of the invention." The claims "fall woefully short," the court said, holding them invalid because they "explicitly cover a scientific impossibility that cannot be made or used by a skilled artisan."

The patent and claims

The '385 patent, titled "Coupler for wireless communications," issued March 23, 2004. Representative claim 1 recites a transmitter and a coupler comprising "a transformer having a non-magnetic core," the coupler "matching the output impedance of the transmitter to the characteristic impedance of the air." Claim 11 requires the transformer to comprise first and second conductive plates, the second "placed underneath and spaced apart from the first conductive plate," and the first "matched to the characteristic impedance of the air at a preselected bandwidth." Claim 18, depending from claim 11, requires the plates to be "formed directly in a chip by deposition of metallic layers onto the chip."

The reexamination and No. 2025-1444

The opinion recites that reexamination rejected claim 1 and upheld claims 11 and 18. In In re Satius Holding, Inc., No. 2025-1444, Satius appealed Patent Trial and Appeal Board decisions rejecting claim 1 on obviousness grounds in ex parte reexamination No. 90/014,826 and denying rehearing. In a nonprecedential opinion, the same panel dismissed that appeal as moot because it had concluded in No. 2025-1446 that claim 1 is invalid.

Why it matters

The opinion treats an expressly claimed impossibility as an enablement defect rather than a definiteness defect, while leaving room for claims so nonsensical that their bounds are unclear. Claims 11 and 18, upheld in reexamination according to the opinion, fell with claim 1 because "claim 1 and its dependent claims explicitly cover" the impossible alternative.

What the court did not decide

The court did not hold that a claim reciting an impossibility can never be indefinite, and it distinguished Synchronoss rather than questioning it. It did not decide whether enablement was properly found waived below, did not review the Board's obviousness rejection, and did not address infringement.

What to watch next

Satius could seek panel rehearing or rehearing en banc in either appeal, or Supreme Court review.

Watch the No. 2025-1446 docket for issuance of the mandate.

Watch reexamination No. 90/014,826 for the USPTO's next action after the dismissal.