I understand that firms like RR are reluctant to manufacture new parts for 60/70 year old engines because of the danger of being sued in the event of an accident.
Just suppose a manufacturer in a country with a relaxed attitude to copyright started producing oddly familar looking V12s and radials that could be bolted onto Spitfires, F4's etc. Or just new replacement parts that would fit elderly engines.
Would the original manufacturer.
A) Try to sue for breach of copyright to get the manufacturer closed down.
or
B) Refuse to acknowledge that the copy was built to their design in order to protect themselves from being sued if one caused an accident.