JPMorgan Chase ($53.55 -0.56%) filled a fund started by billionaire Leonard Blavatnik with risky mortgage securities instead of the conservative investments it was told to make, lawyers for Blavatnik told a New York state judge.

Blavatnik, 55, sued New York-based JPMorgan in New York state Supreme Court in June 2009, accusing the biggest U.S. bank by assets of putting more money into mortgage securities than his investment guidelines allowed.