Federal prosecutors are expected to indict a former chief executive of what was once one of the world's largest investment funds on charges that he signed off on bogus tax shelters designed to save the wealthiest of the wealthy millions, according to the New York Times and the Seattle Times.

The indictment, expected to be released today, will charge Jeffrey Greenstein, former head of Seattle-based Quellos Group, with multiple charges of tax evasion and tax fraud. As recently as 2006, Quellos was on one of the dozen largest "fund of funds" in the world with a portfolio valued around $18bn, but in that year a Senate subcommittee report tied the fund to massive tax evasion, according to the NYT.

The fund would allegedly craft bogus securities transactions designed to fabricate billions in capital losses for tax purposes--perhaps up to $9.6bn in total. Its clients included Robert Wood Johnson IV, heir to the Johnson & Johnson fortune, and Hollywood producer Haim Saban, who produced "The Mighty Morphin Power Rangers," according to the Seattle Times.

Greenstein's lawyers issued a joint statement claiming Greenstein is innocent and will be acquitted at trial. They claim Greenstein is not a tax expert, and that several "world class professionals," including tax experts, blessed the transactions before Greenstein signed off on them. Most of the transactions occurred about nine years ago, the lawyers said.

In 2007, the investment firm BlackRock acquired Quellos and kept Greenstein on as an advisor.