Under what condition can a declaration be used instead of an affidavit?

A declaration can be used instead of an affidavit as permitted by 37 CFR 1.68. This regulation specifies that a declaration is an acceptable form of sworn statement that can replace traditional affidavits in certain contexts related to patent applications. Declarations under this provision must comply with specific formatting and content requirements, ensuring that they fulfill the legal requirements for a formal statement made under penalty of perjury, similar to an affidavit.

In contrast, the other options do not align with the regulatory framework set forth by the USPTO. The first option regarding the timing of filing a declaration relative to a patent's issuance does not reflect any regulatory allowance for substitute documentation. The third option suggests a justification based on the availability of documentation, which is not a recognized basis for opting to submit a declaration instead of an affidavit. Lastly, the fourth option refers to pre-AIA law, which does not correlate with the current rules governing declarations and affidavits.