A person of ordinary creativity, not an automaton (KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 421 (2007)).

Someone able to fit the teachings of multiple patents together (KSR Int'l Co., 550 U.S. at 420).

Able to consider inferences and creative steps employed by a POSITA (KSR Int'l Co., 550 U.S. at 418).

Capable of understanding the scientific and engineering principles of the relevant art (Ex parte Hiyamizu, ).

The inventor's educational level.

Types of problems encountered in the art.

Prior art solutions to those problems.

Rapidity with which innovations are made in the art.

Sophistication of the technology.

Educational level of actors working in the field.

Construing patent claims. For more information on claim construction, see Practice Note, Patent Infringement Claims and Defenses: Evaluating Claim Terminology.

Comparing a patent claim element to an accused product in an infringement analysis under the doctrine of equivalents. For more information on equivalence, see Practice Note, Patent Infringement Claims and Defenses: Doctrine of Equivalents.

Determining whether a pending or issued patent claim would have been obvious in view of the prior art. For more information on obviousness, see Practice Note, Patent Litigation: Obviousness Defense: Motivation to Combine or Modify.

Determining whether a pending or issued patent claim would have been obvious in view of the prior art. For more information on obviousness, see Practice Note, Patent Litigation: Obviousness Defense.

Evaluating whether a pending or issued patent claim meets the written description, enablement, and definiteness requirements. For more information about these specification requirements, see Practice Note, Patent Litigation: Specification Requirements: The Legal Requirements of 35 U.S.C. § 112.

Having ordinary skill in the art (PHOSITA).

Of ordinary skill in the art (POSA).

Skilled in the art.