On November 17, 2021, the IRS reminded users that the Public Key for FATCA filing will expire soon. There is a new key that the IRS will replace on December 3, 2021. After that date, users will have to download the new IRS Public Key from the International Data Exchange System (IDES). When purchasing a new digital certificate or replacing one that is about to expire, users must remember that IDES recognizes and accepts only the digital certificates issued by IRS approved Certificate Authorities (CAs).
Check out these helpful links:
IDES and the new IRS Public Key:
FATCA IDES Resources and Information and IRS Approved CAs: