The chairman of South Korean electronics giant Samsung, Lee Kun-hee, is being sued by his sister.
Lee Sook-hee filed the suit against Mr Lee, 70, over shares their late father left, her lawyer told AFP on Tuesday.
She is demanding the return of assets worth about 190bn won ($169m, £107m), said Yonhap news agency.
The suit is along the same lines as one filed two weeks ago by Mr Lee's brother, Lee Maeng-hee, 80, Ms Lee's lawyer said.
The elder Mr Lee's suit is for 700bn won ($623m; £396m) in shares in the group's flagship, Samsung Electronics, and Samsung Life Insurance, as well as in cash.
According to court documents filed by Lee Maeng-hee, "the stocks... were assets put in a trust under the name of non-heirs, and they should have been apportioned to the heirs according to law".
Lee Kun-hee is accused of keeping the shares for himself.
This is a tale to compete with the most gripping of Korean television dramas, says the BBC's correspondent in Seoul, Lucy Williamson, with allegations of secret shares inside South Korea's most successful electronics company.
"We understand that the matter of inheritance has long since been settled," a Samsung group spokesman told AFP without further details.
The siblings' father Lee Byung-chull, who died in 1987, founded Samsung selling dried fish in South Korea in 1938.
The Samsung Group now includes shipbuilding, telecoms, electronics and construction among its companies, and had a turnover of $220bn in 2010.
Last month, Samsung Electronics reported a 17% rise in profits for the last three months of 2011.
Lee Kun-hee took over the chairmanship of Samsung in 1987. However, in April 2008, he resigned in disgrace after being charged with tax evasion and breach of trust.
He was convicted on the tax charges, but was given a presidential pardon in 2009 and returned to lead Samsung in 2010.
According to the 2010 Forbes Rich List, he was the richest man in South Korea with a personal fortune of $7.9bn.