Blavatnik, who ranks 44th on Forbes list of billionaires, had sought to recover more than $100 million due to JPMorgan's "alleged mismanagement" of his funds during the early stage of the housing crisis of 2007.
In a decision made public on Monday after a three-week trial, New York State Supreme Court Justice Melvin Schweitzer ruled that JPMorgan had breached its contract with Blavatnik's CMMF fund because it exceeded a 20 percent cap for mortgage-backed securities in the fund.
Blavatnik had also argued that JPMorgan had been negligent in its management of the fund. However, Schweitzer said that the bank had acted "reasonably, in light of the information that was available to it at the time."
The ruling was dated Aug. 21.