Allen Kline

Allen Kline, a New York businessman and former manager of the Rolling Stones, Sam Cooke, and Bobby Vinton, heard the Beatles cry for help and answered it.
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John was convinced that Allen Kline could solve all the Beatles business problems.
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Paul eventually gave in to the others insisting and Kline became the Beatles manager on May 8, 1969 though Lee Eastman remained Paul's personal representative.
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Kline did do some good things for the Beatles like getting them higher royaltie rates from EMI.
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Eastman said that the only way Paul could get rid of Kline was to sue the other three Beatles for dissolution of their partnership!