Commit trailer requirements (DCO / co-authors)

Your administrator may require or restrict commit-message trailers. These are enforced per-commit, so a single offending commit anywhere in the pushed range blocks the push — the rejection names the specific SHAs.

Signed-off-by (Developer Certificate of Origin). If sign-off is required, every commit must carry a Signed-off-by: Your Name <you@corp.com> line. Add it as you commit with -s:

git commit -s -m "Fix the thing"          # new commit
git commit --amend --signoff              # add sign-off to the latest commit
git rebase --signoff <base>               # add sign-off across a range

If the policy also requires the sign-off to match the author, the Signed-off-by email must equal your commit author email — set git config user.email to your work address before signing off.

Co-authored-by. Depending on policy, co-author trailers may be banned (remove any Co-authored-by: lines with git commit --amend), required (add a Co-authored-by: Name <email> line), or allowlisted (only approved co-author addresses are permitted — an unapproved one is rejected). The rejection message tells you which case applies and how to fix it.

Both trailers are also recorded on the push record and shown per-commit in the dashboard, so they double as an attribution audit trail even when no policy is configured.