35 U.S.C. · Part II · Chapter 10, Patentability of inventions

35 U.S.C. 103: Conditions for patentability; non-obvious subject matter

In plain English

Section 103 is the US version of the inventive step requirement. Even if no single reference discloses the invention, it cannot be patented if the differences between the claim and the prior art are such that the claimed invention as a whole would have been obvious, before its effective filing date, to a person having ordinary skill in the art.

The analysis follows Graham v. John Deere. The decision maker determines the scope and content of the prior art, the differences between the art and the claim, and the level of ordinary skill, then weighs any objective evidence of nonobviousness, often called secondary considerations: commercial success tied to the claimed features, long-felt but unsolved need, failure of others, copying and unexpected results.

KSR v. Teleflex rejected a rigid requirement for an explicit teaching, suggestion or motivation to combine references. A combination of familiar elements by known methods is likely obvious when it does no more than yield predictable results. The examiner still has to give an articulated reason with a rational underpinning; conclusory statements are not enough. The last sentence of section 103 adds that patentability is not negated by the manner in which the invention was made, so an invention reached by routine testing or by accident is judged the same way as one reached by insight.

Annotation by Raj Sutariya, Co-founder, PatentAssist.ai. General information, not legal advice; the statute below governs.

AIA and pre-AIA

AIA section 103 measures obviousness before the effective filing date of the claim. Pre-AIA section 103, which still applies to applications and patents whose claims all date from before March 16, 2013, measured it at the time the invention was made, and its common-ownership exception in pre-AIA 103(c) now lives in section 102(b)(2)(C).

Text of 35 U.S.C. 103

Current text, quoted from the official United States Code.

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 have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.

Key cases

Graham v. John Deere Co., 383 U.S. 1 (1966). Set out the factual inquiries for obviousness: scope and content of the prior art, differences, level of ordinary skill, and secondary considerations as indicia of obviousness or nonobviousness.
KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007). Obviousness is an expansive and flexible inquiry. Common sense, market pressure and design need can supply a reason to combine, and a finite number of identified, predictable solutions can make a combination obvious to try.

Practical notes

MPEP 2143 lists the rationales examiners use, from combining prior art elements by known methods to obvious-to-try and known work in one field prompting variations in another. Identify which rationale the rejection relies on and test each finding: does the combination really teach every limitation, is there a reason to combine that does not depend on hindsight from your own disclosure, and would the skilled person have expected success?

Evidence beats argument. A declaration under 37 CFR 1.132 showing unexpected results should compare the claimed invention with the closest prior art and be commensurate in scope with the claims; commercial success needs a nexus to the claimed features, not to marketing or price (MPEP 716).

Plan for section 103 when drafting. Record in the specification the problem you solved, why the obvious approaches fail, and any data showing an unexpected effect. Those passages become the backbone of the response when the first rejection arrives.

Related rules and guidance

37 CFR: § 1.104, § 1.111, § 1.132
MPEP: 716, 2141, 2142, 2143, 2144, 2145, 2158