The links below provide information and technical guidance for Software Developers and Transmitters who are interested in developing software for the Modernized e-File (MeF) Forms 1120, 1120-F, and 1120-S for Tax Year 2022. Developers and other Authorized IRS e-file Providers can find information on e-filing returns through MeF in Publication 4163PDF and Publication 4164PDF. Directions for Corporations required to e-file can be found through the e-file for Large and Mid-Size Corporations website. Test Scenarios for the 1120 Form Family can be found on the Modernized e-File (MeF) Assurance Testing System (ATS) Updates page. Extensible Markup Language (XML) Schemas, Business Rules, and Release Memorandum - Throughout the year, multiple versions of these documents may be in use at the same time. Special attention should be paid to the Release Memo issue date and the projected start and end dates for Assurance Testing System and Production. Form 1120 Schemas and Business Rules are now distributed through the Registered User Portal and your e-services mailbox. This mailbox is part of the Secure Object Repository (SOR). Users will access their mailbox in their existing e-services account to pick up the Schemas and Business Rules packages. Instructions for accessing the SOR mailbox Tax Year 2022 Documents Tax Year 2022 1120 MeF Accepted Forms and SchedulesPDF Tax Year 2022 1120 MeF Forms Attachment ListingXLSX Tax Year 2022 1120 MeF Return Due DatesPDF Tax Year 2022 Stylesheets: MeF Stylesheets Tax Year 2022 Known Issues and Solutions XLSM– Revised 03/08/2023 Form 1120, 1120-F, 1120-S links to TY2022 Release Memos Version Available Date ATS Date Production Dates Comments 2022v5.2 02/09/2023 Start: 03/05/2023 End: TBD Start: 03/19/2023 End: TDB Business Rule package updated on 02/24/2023 2022v5.1 11/28/2022 Start: 12/18/2022 End: TBD Start: 01/12/2023 End: TDB Business Rule package updated on 12/23/2022 Business Rule package provided on 12/02/2022 2022v5.0 11/14/2022 Start: 12/11/2022 End: TBD Start: 01/12/2023 End: TDB Updated business rules available on 11/28/2022 2022v4.0 10/13/2022 Start: 11/20/2022 End: 12/11/2022 Not available for Production Not valid for Production 2022v3.0 09/01/2022 Start: 10/24/2022 End: 11/20/2022 Not available for Production Not valid for Production 2022v2.0 07/21/2022 Not available for ATS Not available for Production Not valid for ATS and Production 2022v1.0 06/09/2022 Not available for ATS Not available for Production Not valid for ATS and Production Current Valid XML Schemas and Business Rules for 1120/1120-F/1120-S Modernized e-File (MeF) Schemas and Business Rules