Is a prior art search required before filing a patent application?

No, an applicant is not required to conduct a prior art search before filing a patent application. The MPEP clearly states:

‘An applicant has no duty to conduct a prior art search as a prerequisite to filing an application for patent.’

This is supported by several court cases cited in the MPEP, including:

• Nordberg, Inc. v. Telsmith, Inc.
• FMC Corp. v. Hennessy Indus., Inc.
• American Hoist & Derrick Co. v. Sowa & Sons, Inc.

The ‘inquiry reasonable under the circumstances’ requirement of 37 CFR 11.18 does not create any new duty for applicants to conduct prior art searches. However, applicants and practitioners should be aware that providing false or misleading information during prosecution can jeopardize patent enforceability.