Remember how I said the securities class action accusing JPMorgan of lying to investors about the multibillion-dollar losses of its chief investment office would hinge on when the alleged fraud began? Early filings in the case asserted an unusually short class period, claiming the bank's misrepresentations began only a few months before it revealed its initial $2 billion loss in May. But the first institutional investor to join the fray claimed a much earlier start date, citing the bank's statements and filings from back in 2010. I said the subtext to these different class definitions was who would lead the case, since investor losses depend on the particular class definition and judges typically appoint the shareholder with the biggest losses as lead plaintiff.

That is no longer subtext. In briefs filed Monday night, the only two remaining candidates -- a union fund represented by Robbins Geller Rudman & Dowd and a coalition of public pension funds represented by Bernstein Litowitz Berger & Grossmann, Grant & Eisenhofer and Kessler Topaz Meltzer & Check -- each accused the other of manipulating the class period to win control of the case. Lead counsel fights are always a chance to see how the securities class action bar operates, but the sort of naked maneuvers alleged in these filings are rarely exposed to public view.

Robbins Geller's brief claims that the pension fund coalition didn't lose money at all in JPMorgan trades in the relevant time frame. According to the brief, the public pension funds actually made $25 million in profits in the months between the bank's first assurances that its CIO trading positions weren't overly risky and its admission of losses. And the only reason the public pension funds claim that JPMorgan's fraud dates back to 2010, the Robbins Geller brief said, is because they can't claim losses in the true class period.

That's not the only chicanery the new brief attributes to the pension funds. Robbins Geller, which recently went to war over the lead counsel appointment in the Diamond Foods class action, asserts that Grant & Eisenhofer, as counsel to a Louisiana pension fund, filed what amounts to a dummy complaint solely to extend the class period for the other public pension fund plaintiffs. If it hadn't been for that extension, the brief claimed, the jerry-rigged coalition of pension funds would have had to admit that in the run-up to JPMorgan's admission they actually sold 615,000 more shares than they bought. After filing the dummy complaint, Robbins Geller asserted, the Louisiana fund -- a frequent securities class action filer -- gave way to Ohio funds also represented by Grant & Eisenhofer. The Louisiana fund is not part of the coalition seeking the lead plaintiff appointment; the Ohio funds are. Stuart Grant of G&E told me Robbins Geller's assertion about the dummy complaint is "not worthy of a response."

The pension funds, meanwhile, argued in their new brief that, by any measure, their losses dwarf those of Robbins Geller's union fund client. In the shorter class period, the brief said, the funds lost an aggregate $9.4 million. In the longer time frame, they lost $51.7 million. (It would take someone with better accounting skills than I possess to figure out how Robbins Geller could assert that the pension fund coalition took $25 million in profits in a time period in which the funds claim they lost more than $9 million; if you really want to play with the numbers, here's a filing that details the pension funds' trading in JPMorgan stock over the last two years.)

The pension funds' brief alleges that the union fund is bucking precedent and good sense in arguing for a shorter class period, since the goal of the litigation is to maximize recovery for all shareholders in the class. The union fund's insistence on a short frame and refusal to provide information about its losses in the longer class period "smacks of gamesmanship," the pension funds' brief said. "(It) appears to be part of an effort by (the union fund's) counsel to gain control of the litigation using a truncated class period that disregards the interests of the remainder of the class, which they abandon wholesale."

If the pension funds' accounting of their aggregate losses holds up, they have the upper hand in either class period, especially because, according to their filings, all of the funds except Ohio's lost money even in the shorter time frame. But the Robbins Geller brief also claims that the coalition is a cumbersome, lawyer-driven vehicle that should not be appointed lead plaintiff. Merely coordinating the coalition's meetings, Robbins Geller argued, would cost money that should be going to the class, not to its lawyers.

U.S. District Judge George Daniels of Manhattan is presiding over the case. I'll be very interested to see how long he permits the lead counsel fight to drag on.

(Reporting by Alison Frankel)

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