Question on patent_assignee
In the case of patents whose assignee changes over time, potentially even prior to the patent being granted, how is the patent assignee (assignee_id) listed in the patent_assignee dataset defined?
Is it the patent's first assignee (even if that assignment took place during the patent's examination phase, prior to the patent being granted), the assignee at the time that the patent was granted, or something else?
Thanks!