Can recorded assignment documents be expunged if found to be invalid?

No, recorded assignment documents will not be expunged even if they are subsequently found to be invalid. The USPTO’s policy is to maintain a complete history of claimed interests in property.

As stated in the MPEP: “Office policy regarding recordation of assignment documents is directed toward maintaining a complete history of claimed interests in property and, therefore, recorded assignment documents will not be expunged even if subsequently found to be invalid. See In re Ratny, 24 USPQ2d 1713 (Comm’r Pat. 1992).” (MPEP § 323)

Once a document is recorded with the Assignment Services Division, it will not be removed from the record relating to that application or patent.