An New (Old) Perspective on Claim Construction

In Century Electric Co. v. Westinghouse Electric & Mfg. Co., 191 F. 350 (8th Cir. 1911), the Eighth Circuit had in interesting perspective on claim construction. The Eighth Circuit said that a patent “is a contract made by the acceptance by the government of the offer which the patentee by his application makes to disclose his invention, in consideration that the United States will secure to him the exclusive use and sale of it for 17 years,”

The Court continued:

The offer embodied in the application becomes the specification of his patent, if his offer is accepted, and with his claims evidences the terms of the agreement. Such an agreement is interpreted by the same rules that determine other contracts. The court, should, as far as possible, place itself in the situation of the parties when they made their agreement and then seek to ascertain from the terms of their contract, in the light of the circumstances then surrounding them, what their intention was.

This intention should be deduced from the entire contract and not from any part of it or without any part of it, because they did not agree to it, or to any part of it, without every other part of it. The specification which forms a part of the same application as the claims must be read and interpreted with them, not for the purpose of limiting, or of contracting, or of expanding, the latter, but for the purpose of ascertaining from the entire agreement, of which each is a part, the actual intention of the parties and that intention when ascertained should prevail over the dry words and inapt expressions of the contract evidenced by the patent, its specification and claims.

Modern claim construction seem more rule-bound, and might be improved if animated by the purpose to determine what the inventor invented, not what the claims literally say.