Does it matter who submitted the finding first?

Bug bounties: Yes. The first valid report of that issue is the one that can be paid. Later reports of the same issue are duplicates and are not paid.

Competitions: No. Every finding is scored the same regardless of when it was submitted during the contest. We encourage strong write-ups and submitting once the report is ready, rather than waiting until the last moment.

Related searches: first submitter, who submitted first, race condition, same bug first.