Event when reviewable_claiming is set to false, the automatic claiming happens when performing a moderation action that requires a multiple steps. This helps to address a problem we were seeing where multiple moderators would work simultaneously on the same reviewable item: by automatically claiming it when the first moderator starts editing, revising, or performing other complex moderation actions, subsequent moderators wouldn’t waste time working on the same one.
Any automatically claimed reviewable should be automatically unclaimed when you either finish moderating the reviewable, or cancel out of process.