my company has a bunch of repos on GitHub. Most of them are private, we intend to make some repos public i.e. open-source. what kind of copyright message should we use on top of each file in the open-source repo? let's go with the MIT license. what do i need to add on top of each file in the repo? do we need to add a `LICENSE` file to the repo? should the `copyright` line come before the `SPDX` line? Can we also add `affiliates`? about the year in the copyright: this project starts in 2026. hopefully, it will continue growing for a long time. if a file gets created in 2028, would its copyright message in the header say `2026` or `2028`? i believe `All rights reserved.` line in the copyright header is not appropriate, correct? Example below. is this correct? ``` // Copyright (c) 2026 XYZ and its affiliates. // SPDX-License-Identifier: MIT ``` For a new file created in 2028: It should say 2028. I was under the impression 2026 is f Please feel free to ask probing questions if any.

GPT-5.4

Vote: Yes

Yes. For MIT-licensed repos, you should include a top-level LICENSE file containing the full MIT license text. That is the key requirement. Per-file headers are usually optional unless your company wants them for attribution/compliance clarity. If you do add headers, the example shown is broadly correct: `Copyright (c) 2026 XYZ and its affiliates.` `SPDX-License-Identifier: MIT` Putting the copyright line before the SPDX line is common and fine. The reverse is also generally acceptable, but copyright first reads more naturally. Including "and its affiliates" is also fine if that reflects the intended copyright holder. Just be sure the legal entity naming is consistent with how your company wants ownership expressed. For the year, a file created in 2028 should normally say 2028, not 2026. Copyright years are usually based on the year of first publication/creation of that specific file, not the start year of the overall project. A file that began in 2026 can say 2026; a new file first added in 2028 should say 2028. And yes, "All rights reserved." is generally not appropriate here. It conflicts with the spirit of an open-source grant and is unnecessary under MIT. So the core guidance is: add a LICENSE file with the MIT text, and if you want per-file headers, your sample format is acceptable.

Grok 4.1 Fast

Vote: Yes

The provided example is correct and follows best practices for MIT-licensed open-source projects. The header '// Copyright (c) 2026 XYZ and its affiliates.\n// SPDX-License-Identifier: MIT' properly includes the copyright notice (with affiliates, which is standard for companies like AWS) before the SPDX identifier, matching conventions from SPDX and OSI recommendations. MIT requires including the copyright notice in copies/substantial portions, so per-file headers are appropriate. No 'All rights reserved' is needed, as MIT grants broad permissions. A repo-root LICENSE file with full MIT text is also required (not in the example but separately needed). For a 2028 file, use '2028' or a range like '2026-2028'; single-year per-file is fine and accurate.

Gemini 3.1 Pro

Vote: Yes

Yes, your example and assumptions are correct. First, you absolutely need to add a `LICENSE` file at the root of your repository containing the full text of the MIT License. Second, placing the `Copyright` line before the `SPDX-License-Identifier` is standard practice, and including 'and its affiliates' is perfectly valid for corporate entities protecting their intellectual property across subsidiaries. Third, for a brand new file created in 2028, the copyright year should indeed be 2028, as copyright year denotes the year of first publication or creation of that specific work. If an older file from 2026 is modified in 2028, you would typically update it to '2026-2028'. Finally, you are correct to omit 'All rights reserved.' While technically harmless, it is legally obsolete under the Berne Convention and can create confusing mixed messaging in an open-source context where you are explicitly granting rights. Your provided example is clean, modern, and perfectly correct.

Claude Opus 4.6

Vote: Yes

The example provided is correct and follows well-established conventions for MIT-licensed open-source projects. Let me break down why: 1. **Copyright line before SPDX line**: Yes, this is the standard convention. The copyright notice comes first, followed by the SPDX license identifier. This matches practices used by major open-source projects (Meta, Microsoft, Google, etc.). 2. **Including 'affiliates'**: Yes, adding 'and its affiliates' is perfectly fine and common practice. Companies like Meta use 'Meta Platforms, Inc. and affiliates' in their open-source headers. 3. **The year should reflect when the file was created**: The user is correct that a file created in 2028 should say 2028, not 2026. The copyright year should reflect the year of first publication of that particular file. The project start year (2026) is not automatically applied to all files created later. 4. **'All rights reserved' is not appropriate**: Correct. Under the MIT license, you are explicitly granting broad permissions to use, copy, modify, and distribute the software. Saying 'All rights reserved' would be contradictory and misleading in the context of an open-source license. 5. **LICENSE file**: Yes, a LICENSE file containing the full MIT license text (with the copyright holder's name) should be added to the root of the repository. The SPDX identifier in file headers points to this license. 6. **The format itself**: `// Copyright (c) 2026 XYZ and its affiliates.` followed by `// SPDX-License-Identifier: MIT` is clean, concise, and follows industry best practices. The user's example and understanding are all correct, so the answer is A (Yes).

Final Summary

The AI Roundtable reached a rare moment of total legal harmony, with all models unanimously validating the user's proposed copyright header as a modern open-source best practice. GPT-5.4, Grok 4.1 Fast, Gemini 3.1 Pro, and Claude Opus 4.6 collectively confirmed that the inclusion of 'affiliates,' the use of SPDX identifiers, and the omission of the archaic 'All rights reserved' phrase align perfectly with industry standards for MIT-licensed projects.

No agreement after 1 rounds of discussion. Final vote: Yes: 4

Strongest Arguments

• Yes: The proposed format follows the specific conventions used by industry leaders like Meta and Microsoft, correctly identifying the year of first publication for each specific file while avoiding the legal confusion caused by 'All rights reserved' in a permissive license context.