[1] As of 2019, he was in a long-running litigation to regain control of companies he founded from his ex-wife and three children, or failing that, around $400 million in back pay.
Grynberg made his first million dollars by the age of 30 when he formed a company, Oceanic Exploration Co., that reworked a previously drilled gas well that had been abandoned by Amerada Hess Corporation as "noncommercial".
His reworked well led to the discovery of the Nitchie Gulch gas field in Wyoming, leading Grynberg to become a millionaire in 1962.
[citation needed] The Kashagan Field is estimated to hold 9 billion barrels (1.4×109 m3) of recoverable oil and 25 trillion cubic feet (710 km3) of natural gas.
Grynberg was one of the first western oilmen to develop relations with Kazakh President Nursultan Nazarbayev before the collapse of the Soviet Union.
[citation needed] According to court records, it was Grynberg who provided the introductions and data for BG, BP, Statoil, ARCO, Transworld Oil and others to enter the region in the late 1980s and early 1990s.
[7] Grynberg has been focused on a Qui Tam lawsuit against the major oil companies accusing them of stealing billions of dollars in royalties from the U.S.