How does insolubly ambiguous differ from ordinary claim construction disputes?

Ordinary disputes allow a narrowing construction even if difficult. Insolubly ambiguous claims permit no such construction at all, rendering them indefinite and invalid.

Does the presence of some ambiguous terms automatically invalidate a patent claim?

No. Claims survive if they remain amenable to a reasonable construction that defines the invention's scope for a skilled artisan.

What role does intent play when terms are left open in a sale of goods?

Under UCC 2-204(3), intent to contract plus a reasonably certain remedial basis prevents failure for indefiniteness even if essential terms remain open.

Legal Term

insolubly ambiguous

/in-SOL-uh-blee am-BIG-yoo-uhs/

Also known as: insolubly ambiguity · indefiniteness · 35 U.S.C. § 112

Written by attorneys · grounded in primary & secondary sources — see below

in patent law
A standard for assessing patent claim indefiniteness. A claim meets this standard when its language is so unclear that no reasonable narrowing construction exists to permit a person of ordinary skill in the art to discern the invention's boundaries.

Sources & Authorities· 2 primary sources

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Uniform Acts

Restatements

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How it applies

Common Examples

2

Indefinite Contract Terms Still Enforceable

Iris Irons emailed Imperial Motors offering to buy 500 custom engine mounts at a price to be set after market surveys. Imperial Motors replied accepting the order without specifying price or delivery dates. When Imperial Motors later refused to ship, Iris sued. The court found the terms open but the parties' intent clear and a remedy possible under trade usage, so the agreement held despite the ambiguity.

Patent Claim Lacks Definable Scope

Icarus Aviation obtained a patent on optical fiber with a core refractive index described only as 'substantially matching' the cladding. Sumitomo Electric challenged the claim during infringement litigation. The court examined whether any construction could clarify the boundary between matching and non-matching indices. Finding no such construction possible, it held the claim invalid.

Seen in the casebook

Key Cases Using This Term

1

In re Alappat

Put it into practice

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