4.1 The Graham Factors & KSR Obviousness Framework

4.1 The Graham Factors & KSR Obviousness Framework

Statutory Foundation: 35 U.S.C. § 103

35 U.S.C. § 103 sets forth the statutory requirement of nonobviousness, which serves as one of the fundamental hurdles for patentability under U.S. patent law. Under the America Invents Act (AIA), applicable to applications having an effective filing date on or after March 16, 2013, 35 U.S.C. § 103 provides:

"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."

For pre-AIA applications (effective filing date prior to March 16, 2013), section 103(a) evaluated obviousness "at the time the invention was made" rather than before the effective filing date. Crucially, under both AIA and pre-AIA law, the obviousness inquiry must evaluate the claimed invention as a whole. Examiners and practitioners are strictly forbidden from engaging in hindsight reconstruction—the improper practice of using the applicant's disclosure as a roadmap to combine prior art elements to recreate the invention.

The Four Graham v. John Deere Factual Inquiries

In the landmark decision Graham v. John Deere Co., 383 U.S. 1 (1966), the Supreme Court established that while the ultimate determination of obviousness is a legal conclusion, it rests upon four mandatory factual inquiries:

1. Determining the scope and content of the prior art: Identifying references that qualify as prior art under 35 U.S.C. § 102 and fall within the pertinent technical field or address the specific problem solved by the invention.
2. Ascertaining the differences between the prior art and the claims at issue: Comparing the scope of the claimed subject matter element-by-element against what is disclosed in the prior art references.
3. Resolving the level of ordinary skill in the art: Establishing the background knowledge, education, and experience of a Person Having Ordinary Skill In The Art (PHOSITA/POSITA) at the relevant time (MPEP § 2141.03).
4. Evaluating objective evidence of nonobviousness (secondary considerations): Assessing evidence such as commercial success, long-felt but unsolved need, failure of others, copying by competitors, and unexpected results.

The Supreme Court's Landmark Decision in KSR v. Teleflex

For decades following Graham, the U.S. Court of Appeals for the Federal Circuit applied the "Teaching, Suggestion, or Motivation" (TSM) test, holding that a claim could only be rejected as obvious if the prior art explicitly or implicitly contained a teaching, suggestion, or motivation to combine the references.

In KSR International Co. v. Teleflex Inc., 550 U.S. 398 (2007), the Supreme Court unanimously rejected the rigid application of the TSM test as the sole standard for obviousness. The Court reinstated an expansive and flexible approach, emphasizing that:

• Common sense, design incentives, and market demand must be considered alongside explicit teachings.
• When a work is available in one field of endeavor, design incentives or market forces may prompt variations of it for use in the same field or a different one.
• If a technique has been used to improve one device, and a person of ordinary skill in the art would recognize that applying it to a similar device would yield predictable results, the combination is likely obvious.
• "Obvious to Try" Standard: Under KSR, an invention may be obvious to try where there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, such that a POSITA has a reasonable expectation of success.

MPEP § 2143: The Seven Rational Underpinnings

Following KSR, the USPTO promulgated MPEP § 2143, establishing seven explicit rational underpinnings that an Examiner may invoke to support a prima facie rejection under 35 U.S.C. § 103:

1. Combining prior art elements according to known methods to yield predictable results.
2. Simple substitution of one known element for another to achieve predictable results.
3. Use of known technique to improve similar devices, methods, or products in the same way.
4. Applying a known technique to a known device, method, or product ready for improvement to yield predictable results.
5. "Obvious to try" — choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success.
6. Known work in one field prompting variations for use in either the same field or a different field based on design incentives or market forces, where the variations are predictable to a POSITA.
7. Some teaching, suggestion, or motivation in the prior art that would have led a POSITA to combine the teachings or modify the references.