Kingsfield · Research · Intellectual Property

Can a patent be denied as obvious even when no single prior art reference shows the whole invention?

Published 2026-06-23 · U.S. federal law

Section 103 denies a patent when the differences between the claimed invention and the prior art would have made the invention obvious to a person of ordinary skill in the art, even if no single reference shows the whole thing.

The answer

The obviousness bar

35 U.S.C. § 103 bars a patent if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious, before the effective filing date, to a person having ordinary skill in the relevant art. Obviousness can rest on a combination of references, not just a single anticipating disclosure.

Judged as a whole, by the ordinary artisan

The statute fixes the viewpoint as a person of ordinary skill in the art and directs the inquiry to the claimed invention as a whole. It also provides that patentability is not negated by the manner in which the invention was made.

The judged input

What the AI drafted

Submitted to the judge

This is an excerpt from a draft patentability opinion letter — the kind of work product a lawyer generates with a legal-AI drafting tool, then has to stand behind. Kingsfield does not write it; it rules on the citations the model put in it. This draft cites two authorities; one of them is wrong.

AI draft excerpt — patentability opinion letter

We advise that the proposed claims face material risk under the obviousness doctrine even though no single reference discloses every element. Under 35 U.S.C. § 103, a patent may not issue if the differences between the claimed invention and the prior art are such that the invention as a whole would have been obvious to a person of ordinary skill in the art before the effective filing date. The combination of the two cited references supplies each limitation, and a skilled artisan would have had reason to combine them. We note that this obviousness bar is distinct from the anticipation rule of 35 U.S.C. § 102.

The judge ruled on every citation as the draft used it — it accepted 35 U.S.C. § 103 and rejected 35 U.S.C. § 102. Here is why.

The verdict

How Kingsfield ruled

Ruled 2026-06-23

Each citation in the draft above was submitted to the Kingsfield judge and ruled against the primary-law corpus — Accept, Reject, or Inconclusive, per citation. These are live verdicts, not editorial. Each card shows the claim the draft made and the verbatim authority the verdict was rendered against.

Accept35 U.S.C. § 103

The draft claimed: A patent may not be obtained if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date to a person having ordinary skill in the art.

“§ 103. Conditions for patentability; non-obvious subject matter A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would h”

Cite found; proposition supported by the cited text.

Reject35 U.S.C. § 102

The draft claimed: Section 102 is the provision under which a claim is unpatentable because, although no single prior art reference shows the whole invention, the combined differences would have been obvious to a person of ordinary skill in the art.

Cite found, but the cited text does not support the claim. 35 U.S.C. 102 governs novelty and anticipation, which require a single prior art reference disclosing the claimed invention; the obviousness inquiry based on combined prior art differences is at 35 U.S.C. 103. Regenerate with the correct authority.

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Kingsfield rules on every citation, quote, and proposition your AI produces, against the primary law we cover. Accept, Reject, or Inconclusive, per citation, with a signed Audit Capsule.

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This page is legal information, not legal advice, and does not create an attorney-client relationship. The draft shown is an illustration of a typical AI answer; verdicts reflect the cited authority in the Kingsfield corpus as of the ruling date shown above.