Hightower, 64, says De Niro, 75, has kept her in the dark about money since 2008.
She believes she is entitled to a cut of his 38 movies and 35 new business ventures since 2004.
Besides De Niro’s Hollywood income, there's earnings from his Nobu restaurant chain and Greenwich Hotel ownership......
The couple’s revenue increased since their pre-nup at $300 million — ($250 million came from movies).
It is now estimated De Niro’s net worth is $500 million.