The Federal Circuit recently released its opinion for the case In re Packard, providing guidance as to when the United States Patent and Trademark Office (USPTO) may properly reject a claim as failing to meet the definiteness requirements of 35 U.S.C. § 112. The patent at issue in the case was rejected because the examiner determined that several claim limitations lacked antecedent basis or were otherwise unclear. The court held that the when the USPTO has made a well-grounded rejection that clearly identifies the language in a claim that is ambiguous or unclear, it may properly reject the claim as failing to meet the requirements of § 112 if the applicant does not offer a satisfactory response.

In upholding the rejection of the patent in suit, the Federal Circuit found that Mr. Packard’s response to the § 112 rejection was inadequate for several reasons. The response did not address all of the § 112 issues presented by the examiner. For the issues that were addressed, the response only offered an explanation of the written description and the figures and did not discuss the claim language. The response also failed to propose amendments to clarify the claim language or make arguments to show why the existing claim language was not indefinite.

In addition to stating why Packard’s offered response was inadequate, the Federal Circuit also provided guidance as to what it considers to be a satisfactory response. A satisfactory response should include either a modification of the language regarded as unclear, a separate definition of the unclear language, or an explanation of why the language is not actually unclear.