Grant was instrumental in setting up Led Zeppelin's publishing company, Superhype Music in 1968. He was also the driving force in establishing Swan Song Records in 1974, which gave Led Zeppelin further financial and artistic control over its products. Although initially he solely managed Led Zeppelin, in later years he additionally assumed management of other bands signed to Swan Song, such as Stone the Crows, Bad Company and Maggie Bell. In 1975 he turned down a lucrative offer to manage Queen. When he was once questioned on what was the single most important thing a manager could say, Grant's response was "Know when to say 'no'." In 1977, he was asked by Colonel Tom Parker to manage a proposed concert tour of Europe by Elvis Presley, but Elvis died on 16 August 1977, just as negotiations had commenced.