Refers to a statement in the US Supreme Court Decision White v. Dunbar, 119 U.S. 47 (1886)
“Some persons seem to suppose that a claim in a patent is like a nose of wax, which may be turned and twisted in any direction, by merely referring to the specification, so as to make it include something more than, or something different from, what its words express. The context may undoubtedly be resorted to, and often is resorted to, for the purpose of better understanding the meaning of the claim, but not for the purpose of changing it and making it different from what it is. The claim is a statutory requirement, prescribed for the very purpose of making the patentee define precisely what his invention is, and it is unjust to the public, as well as an evasion of the law, to construe it in a manner different from the plain import of its terms.”
Which in turn refers to Victorian melodrama’s taste for extensive makeup and changing the shape of an actor’s features for different roles. The phrase “nose of wax” has come to be very popular in patent litigation – and is often used in a variety of ways. Thus in the 1970s case Sterner Lighting, v. Allied Electrical Supply, the Fifth Circuit (before the formation of the Federal Circuit) declared that:
“[a] patent may not, like a ‘nose of wax,’ be twisted one way to avoid anticipation and another to find infringement.”
The phrase “nose of wax” is mostly used to say that a patent holder may not construct (construe) the claims of a patent in two different ways, one to claim infringement, the other to uphold validity (except, it seems, in the German split system.)