The Investigative Committee announced on May 7 that Bosov, 52, had died the previous evening of a gunshot wound to the head.
A pistol was reportedly found near the body.
Bosov was a major shareholder and board of directors chairman of the Alltek group, which controls the coal producers Siberian Anthracite, VostokUgol, and other firms.
According to the Forbes billionaires’ list, Bosov was the 86th-richest Russian, with a fortune estimated at $1.1 billion.
The RBK news agency quoted acquaintances of Bosov’s as saying his affairs had been in turmoil since the beginning of the year, when he began moving assets around and dismissing employees.
Early last month, Bosov dismissed his partner in the VostokUgol coal company, Aleksandr Isayev, for purported abuse of his position and embezzlement. Isayev has filed a defamation suit.
On May 1, it was reported that a former employee of the Genius Fund Group, an investment firm controlled by Bosov that is active in the legal marijuana business in the United States, had filed a civil suit against Bosov in Los Angeles seeking more than $1 million for alleged breach of contract. The complainant, Francis Racioppi, is a U.S. Army Special Forces veteran.