Most welding standards, with the exception of NAVSEA standards, recognize WPSs and supporting PQRs are intellectual property. Companies that are wholly owned or that are subsidiaries of the parent company can share intellectual property. Therefore they can share the welding documents. Companies that have multiple divisions are beginning to establish corporate wide welding programs for just that reason.
When Company A purchases Company B, it also becomes owner of Company B's intellectual property, thus all of Company B's welding documents become the property of Company A. The letterhead is changed to reflect the new ownership and all is good in "Welding Land.”
Best regards - Al