How does the USPTO handle arguments about improper hindsight in obviousness rejections?

Applicants often argue that an examiner’s obviousness rejection is based on improper hindsight reasoning. MPEP 2145 addresses this issue:

“Applicants may argue that the examiner’s conclusion of obviousness is based on improper hindsight reasoning. However, ‘[a]ny judgment on obviousness is in a sense necessarily a reconstruction based on hindsight reasoning, but so long as it takes into account only knowledge which was within the level of ordinary skill in the art at the time the claimed invention was made and does not include knowledge gleaned only from applicant’s disclosure, such a reconstruction is proper.’ In re McLaughlin, 443 F.2d 1392, 1395, 170 USPQ 209, 212 (CCPA 1971).“

Key points about hindsight arguments:

• Some degree of hindsight is inherent in obviousness analyses
• Proper hindsight uses only knowledge available to a person of ordinary skill at the time of invention
• Improper hindsight relies on knowledge gleaned solely from the applicant’s disclosure
• Examiners should explain how their reasoning is based on prior art teachings, not applicant’s disclosure
• Lack of express motivation to combine in prior art doesn’t necessarily mean improper hindsight was used

Examiners should carefully articulate their reasoning to show they are not relying on improper hindsight.

To learn more:

• hindsight
• obviousness
• patent examination
• prior art