Durus Capital Management

, the hedge fund that made a habit of "inadvertently" buying up big stakes in small companies over the last few years, has reached a settlement with a second company over allegations of improper trading.

The hedge fund is paying $32.2 million to

EsperionTherapeutics

(ESPR) - Get Report

to settle a lawsuit with the Ann Arbor, Mich., company filed last summer. The company had sued to recover short-term profits Durus made trading Esperion stock under a little-known securities regulation that applies to large shareholders.

Back in October, Durus made a $5.1 million payment to

Allos Therapeutics

( ALTH) to resolve a similar short-term trading claim arising out of Section 16-b of the Securities Exchange Act of 1934.

The settlement with Esperion comes two weeks after

Pfizer

(PFE) - Get Report

announced a $1.3 billion deal to buy Esperion, which manufactures an experimental drug that may boost good cholesterol levels.

The Pfizer acquisition represented a major windfall for investors in the Durus fund, which owns a 30% equity stake in Esperion. Based on Pfizer's proposed $35-a-share purchase price, the Durus fund's stake in Esperion is valued at $350 million.

The Durus fund, managed by Scott Sacane, had acquired most of those shares over the past year, but didn't disclose its large holding until last July. Sacane has blamed the big stock purchases on "inadvertent buying" andsaid he hadn't meant to circumvent any stock ownership disclosure rules by not disclosing his large holdings.

But others saw something more sinister -- an attempt to quietly manipulate the price of Esperion, which historically has been a thinly traded stock.

Sacane has offered a similar explanation for how Durus managed to acquire a 77% state in another small health care company,

Aksys

(AKSY)

. Like Esperion, Askys also filed a lawsuit seeking to recover any short-term profits Durus made trading its stock.

The Boston office of the

Securities and Exchange Commission

is investigating Durus' trading activities. Meanwhile, the investors in the Durus fund have since put Sacane on a short leash. In September, Durus investors ousted Sacane's handpicked board and installed their own directors to keep an eye on Sacane and handle the negotiations with the companies suing the fund.

In early afternoon trading, shares of Esperion were virtually unchanged at $34.58. Aksys stock rose 15 cents, or 1.7%, to $9.17.

Harry Davis, an attorney with Schulte Roth & Zabel, who represents the Durus investors, said the fund is trying to negotiate settlements with Aksys and another company that has filed a lawsuit,

Novoste

(NOVT) - Get Report

."We are committed to finding an amicable solution,'' he said.

The settlement with Esperion must still be approved by the Connecticut federal judge overseeing the case.