Yoko Ono has sued two music companies in the US for $10m (£5.35m), claiming she is owed royalties from sales of her late husband John Lennon's records.
Ono's lawyer declined to comment on the case
The claim, filed in Manhattan's Supreme Court, accuses EMI and its subsidiary Capitol Records of "willfully and knowingly under-reporting royalties".
EMI/Capitol spokeswoman Jeanne Myer said there are "sometimes differences of opinion" on royalties.
But Ms Myer refused to comment specifically on the Ono case.
Ono's file claims that EMI and Capitol hid the "true use and disposition of Lennon's recordings".
The papers also accuse the record companies of "intentionally and systematically rendering dishonest and grossly deficient accounting statements".
Ono's lawyer, John LiCalsi, refused to comment on the case.
Ms Myer added: "Artists from time to time request audits of their royalty accounts".
She said contracts are sometimes subject to interpretation, "but 99 times out of 100 these things are resolved in an amicable way".