SAN FRANCISCO (AP) – The sons of rock music impresario Bill Graham are suing the executor of the late promoter’s estate, saying he’s concealing memorabilia treasures from heirs in order to enrich himself.

The San Francisco federal court lawsuit filed Wednesday says the late concert promoter and rock manager, who died in a 1991 helicopter crash, left a vast personal collection of music memorabilia, including concert posters, scrapbooks and other items.

David Graham and Alexander Graham-Sult claim Nicholas Clainos, former president of Bill Graham Enterprises, cheated them out of the treasures.

The San Francisco Chronicle reported Clainos failed to disclose the items to Graham’s heirs or to a probate judge and instead transferred them to Bill Graham Enterprises for a lucrative sale.

The sons said they found records of the transactions last year. 

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