West L.A. patent monetization firm Marathon Patent Group Inc. will merge with Uniloc Luxembourg, a competing European company, in coming months, the companies announced Friday.

The merger, which is subject to approval by stockholders of both companies, the federal government and Nasdaq, is expected to close later this year or in the first quarter next year, according to a press release. Upon completion of the stock swap, Uniloc shareholders will control 55 percent of the new company, to be called Marathon Group SA, and Marathon shareholders will own the balance.

Marathon and Uniloc are both in the business of buying patent rights from inventors, entrepreneurs and existing companies. They pursue, often through litigation, businesses that could be making, using or selling products or services that in some way rely on patent-protected materials.

Marathon owns 381 patents and is involved in litigation with 45 defendants; Uniloc is bolstered with 281 patents and has litigation against 74 defendants, according to information compiled for investors.

Doug Croxall, Marathon’s chief executive, will continue in that role upon completion of the merger.

“This combination positions Marathon Group for greater success than either company could have achieved independently,” Croxall said in a press release. “Our common culture of a lean workforce, commitment to providing a return on innovation and an international platform, are the foundations for the future success of the company.”

Craig S. Etchegoyen, Uniloc’s chief executive, will become the chief intellectual property officer of the combined company.

The principals declined further comment about the merger on Monday.

Marathon’s stock fell more than 13 percent Monday to close at $2.53.

For more information about Marathon, check out recent coverage by the Business Journal here.