Activating new products, what about patches already applied?

Hi, a customer who has been running EBS for a couple years, is about to implement additional products.  I know we must use License Manager to activate them, but my concern is: all this time, those products have had status of not installed, and we have applied several (RUPS, family packs, individual, etc.) patches, and supposedly those products have not been updated because of that.

Now, after we change their status to installed, do we need to "reapply" all those patches, or is there something else we should do?

Thanks!

Hiroshi Komatsu