While USA Truck is in the midst of an attempted financial turnaround, no investor has been more active in gobbling up shares of the Van Buren-based trucking firm than Stone House Capital LLC, an investment firm based in New York City.

Since Oct. 22, the firm, led by Mark Cohen, has purchased more than 1.5 million shares of USA Truck stock. Stone House now is the largest shareholder of USA Truck, beginning with a single purchase of 900,00 shares.Baker Street Capital holds 1.4 million shares, Knight Transportation of Phoenix owns 1.3 million shares and Grace & White increased its stake to 1.1 million shares. Knight has expressed interest in acquiring USA Truck and offered in September $9 per share as part of a deal valued at $242 million.

With last week’s purchase of 50,000 shares Stone House in now just under the 15 percent threshold that would trigger a shareholder-rights plan or “poison pill.” The poison pill was put into place in hopes of warding off an unwanted takeover.

Members of the USATruck board have a 10-day window to decide if they want to waive the poison pill. Because of a pending lawsuit against Knight and the need for stability during the turnaround process it seems unlikely that USA Truck would elect not to protect itself.

Why Stone House has become so enamored with USA Truck is unclear.

Multiple attempts since October to reach Cohen, hailed in 2013 by Institutional Investor as a “rising star” among hedge fund operators, have been unsuccessful.

Cohen is described in a 152-word Institutional Investor profile as a 31-year-old graduate of the University of Pennsylvania’s Wharton School of Business who likes to “run a concentrated portfolio and doesn’t fear volatility.”

Stone House, according to the Cohen profile, has topped a 43 percent return as “a long-short equity fund” since it was created. Cohen incorporated the firm with the Delaware secretary of state’s office in 2010. Beyond that initial filing there is little information on the company on record in Delaware where Stone House has an annual tax assessment of $250.

It is difficult to find much about the investment firm or its founder, otherwise. Online profiles of Stone House, compiled using documents on file with the Securities and Exchange Commission, outline a medium-sized investment firm managing less than $50 million.

Up to this point USA Truck has seen little to suggest that Stone House Capital is interested in overthrowing its leadership or attempting a takeover. USA Truck Chief Financial Officer Cliff Beckham described Stone House’s involvement as “supportive.”

“They do own a lot of stock, but they have not become activists,” Beckham said. “It’s a supportive and congenial business relationship.”

Numbers from the fourth quarter - likely to be released within the next month - should provide more evidence of where USA Truck stands financially. There have been signs of progress, such as trimming third-quarter losses by more than $5 million between 2012 and 2013, but it is unclear if the company will post a quarterly profit for the first time in more than two years.

Stock in the trucking and transportation firm, however, has been popular among investors over the past two plus months. During the past 52 weeks, the stock has traded as high as $16.38 after being valued as low as $3.42 per share over the same time frame.

Business, Pages 23 on 01/14/2014