Can an affidavit under 37 CFR 1.131(a) be used to overcome all types of rejections?

No, an affidavit under 37 CFR 1.131(a) cannot be used to overcome all types of rejections. MPEP 715.01(a) specifically states:

Note that an affidavit or declaration under 37 CFR 1.131(a) cannot be used to overcome a rejection based on a U.S. patent or U.S. patent application publication naming a different inventive entity which claims interfering subject matter as defined in 37 CFR 41.203(a). See MPEP § 715.05.

This means that if the reference is a U.S. patent or patent application publication with a different inventive entity and claims interfering subject matter, a 1.131(a) affidavit is not applicable. In such cases, other procedures, such as an interference proceeding or a derivation proceeding, may be necessary to resolve the conflict.

To learn more:

• 37 CFR 1.131(a)
• affidavits
• interfering subject matter
• rejections

To learn more:

• 37 CFR 1.131(a)