The government agency, which runs the scheme, rejected the application by supporters of the founder of Scientology after its blue plaques panel decided that it was unconvinced about Mr Hubbard's "reputation".
The decision has frustrated the Hubbard Foundation, which had nominated him. In an unusual move, a foundation representative went to visit English Heritage officials, following the verdict, to find out more about why he had been rejected and how his case could be helped.
The organisation, which is considered a cult by some, is based on the premise that the human race is descended from Thetans, an exiled race from another planet....