[angkor]

I would contend that there are 4 surviving Beatles, the 4th being the “5th Beatle” Sir George Martin, who had indisputable influence on the band and was (in only one example) directly responsible for orchestral additions over several albums.

[La Lydia]

Don’t you mean 3?

[curth]

Murray the K called himself the fifth Beatle too. Only three humans alive,Paul, RIngo and Pete can call themselves former Beatles and as important a part as George Martin played in their success, he was not and never will be a Beatle.