Once files have been migrated from old iMac to new MacBook Pro, can I scrub the old iMac?

Yes you can, however please always verify the new Mac is working perfectly and your migration went well before doing so. To "scrub" it please follow the steps in What to do before you sell, give away, or trade in your Mac.

hutsonlm wrote:

Once files have been migrated from old iMac to new MacBook Pro can I safely scrub the iMac?

Yes, but be sure to refer to this advice in the "Related Article:" "If you're not keeping your old Mac, learn what to do before you sell, give away, or trade in your old Mac."