How long does the US duty of disclosure last?

Question

37 CFR 1.56 says:

The duty to disclose information exists with respect to each pending claim until the claim is cancelled or withdrawn from consideration, or the application becomes abandoned.

Therefore, questions are:

1. Are claims "pending" until the date of issue (i.e. still after notice of allowance, and after issue fee is paid)?
2. What happens if you come across material information (e.g. a search report from a foreign office action) the day before the patent issues (or immediately before whatever the appropriate duty of disclosure deadline is)? Must you disclose it/withdraw and file an RCE/etc., or is it not necessary to disclose, e.g., due to the "3 month" period that is often referenced with respect to IDSes?

Answer 1

The duty does not end at allowance - From the MPEP 2001.04 Information Under 37 CFR 1.56(a) [R-08.2017]

37 CFR 1.56(a) states that the duty to disclose information exists until the application becomes abandoned. The duty to disclose information, however, does not end when an application becomes allowed but extends until a patent is granted on that application. The rules provide for information being considered after a notice of allowance is mailed and before the issue fee is paid (37 CFR 1.97(d)) (see MPEP § 609.04(b), subsection III). The rules also provide for an application to be withdrawn from issue:CFR 1.56(a) states that the duty to disclose information exists until the application becomes abandoned. The duty to disclose information, however, does not end when an application becomes allowed but extends until a patent is granted on that application. The rules provide for information being considered after a notice of allowance is mailed and before the issue fee is paid (37 CFR 1.97(d)) (see MPEP § 609.04(b), subsection III). The rules also provide for an application to be withdrawn from issue:

Answer 2

It lasts until the patent issues, which occurs both after notice of allowance and issue fee payments. See MPEP 2001:

The duty to disclose information, however, does not end when an application becomes allowed but extends until a patent is granted on that application.

However, per the "intelproplaw" links in the comments of another answer ([1], [2]), such disclosures filed near issue date may be ineffectual (i.e. examiner won't consider them) beyond cleansing one's hand of inequitable conduct issues.

Answer 3

Technically the duty ends when prosecution closes (after notice of allowance) but it's still a good idea to submit an RCE with the new reference before it issues.