via https://www.zerodayinitiative.com/blog/2019/1/14/pwn2own-van...

> If more than one contestant registers for a given category, the order of the contestants will be drawn at random. Based on the contestant order, the first contestant will be given an opportunity to attempt to compromise the selected target. If unsuccessful, the next randomly drawn contestant will be given an opportunity. This will continue until a contestant successfully compromises the target. The first contestant to successfully compromise a selected target will win the prize money for that target in that category. After a target has been compromised, the contest for that category is over and no other contestants will participate in the contest for that category (unless Sponsor has offered an additional winner option, which would be announced at the conference if applicable).