Royal Warrants
The King and the Prince of Wales are able to bestow ‘Royal Warrants’ on suppliers of goods and services. This allows the warrant holder to display the coat of arms of the royal personage in question and the text ‘Supplier of widgets (or whatever) to His Majesty the King (or whomever).
A supplier must have been providing the service for at least five years before the warrant is considered, and are highly prized as a recognition of excellence, being described as ‘A Peerage for Trade’. They can, however, can be revoked at any time.
Harrods famously had Royal Warrants since 1910, but these were withdrawn in 2001 following Harrods’ owner Mohammed Fayed’s long running accusations against the royal family (particularly the Duke of Edinburgh whom he has banned from the store) regarding their alleged involvement in the deaths of Princess Diana and Fayed’s son Dodi. Harrods actually pre-empted any palace decision by removing the warrants from the store saying “Since neither the Queen nor Prince Charles have shopped in Harrods for several years, displaying the royal crest would be totally misleading and hypocritical.”
A full list of Royal Warrant holders can be found at the Royal Warrant Holders Association website here.