This is a bill-of-review case challenging a default judgment. The defendant had moved without updating its registered address with the Secretary of State. Notice of the default judgment was sent, at the plaintiff's request, to that out-of-date registered address. The defendant filed a bill of review, introducing evidence suggesting that the plaintiff had actual knowledge of the new business location, making that, and not the "registered" address, the "last known mailing address" for purposes of the rules. The Supreme Court holds that the plaintiff's actual knowledge of this new address would subject the default judgment to attack.