Understanding Lead Partition Assignment

[Anonymous]

I have a question around assigning leads to partitions. I have 3x region based workspaces and partitions for EMEA, NA and APAC regions plus a Default workspace that sees all lead partitions. If a lead fills in a form as part of an EMEA workspace campaign, does that lead automatically drop into the EMEA Partition? Or do the assignment rules in Admin tell it what partition to put it into?

Thanks