How should be a SPDX license name when extracting from another file content?

Question

Following the SPDX simple license expressions and the License identifier field example, when creating a custom license that's not listed in licenses list (including exception), I could use LicenseRef-ACME, where ACME is my company name, or even, my project name in a repository.

However, when having to extract a license text from a header, to distribute that custom license as a separated file, I'm not sure about:

• The license name that should be used (e.g. LicenseRef-ProjectName)
• The license file name that should be used (e.g. LICENSE)
• Custom fields in the license file to refer where I extract that text.

I read about DocumentRef, but I'm not sure if it's the case, and how to use it.

Answer 1

I use reuse to validate my SPDXing and it's happy with the following:

1. Using LicenseRef-ProjectName. Unless your work is owned by a company and you're planning on using the same license for all your projects, in which case LicenseRef-CompanyName will indicate that to your customers.

2. I create LICENSES/LicenseRef-ProjectName.txt (reuse requires a copy of each license in the LICENSES folder).

3. No custom fields are required. The license file should be just the license text.

Then in a file using that license I use:

# SPDX-License-Identifier: LicenseRef-ProjectName
# SPDX-FileCopyrightText: Copyright 2023 A. P. Hacker

Using a validator and simply following their guidelines can take some of the administrative burden off your shoulders.