https://www.irs.gov/tax-professionals/1120x-ty2023v3-point-0-release-memo
1120x TY2023v3.0 release memo | Internal Revenue Service
The 1120x TY2023v3.0 Release Memo provides information to software developers and/or transmitters about the release of schemas and business rules for tax year...
releasememointernalrevenueservice