The advice that I have received in the past is two-fold:

(a) make whatever attempts that you can to identify a legal entity that may have taken over responsibility for the company's assets (this would include their trial records). For example, Companies House are able to provide a history of dissolved companies in order to identify company acquisitions. It is important to retain a record of attempts made to identify the owners.

(b) contact the MHRA to give them the opportunity to receive the data. Depending on the status and history of any marketed products that the data support, they may wish to retain the data. If the data has never supported any marketed products or the products have not been on sale for a number of years, they may not wish to retain the data and it can be destroyed.

It would be unwise to destroy the data before carryng out the investigations described above. Industry practice suggests that it is acceptable for a storage company to destroy the records if all attempts to identify an owner have failed and the MHRA do not wish to retain the data.