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Uniloc USA Inc., an accused patent troll best known for winning a nearly $400 million verdict against Microsoft Corp. in 2009, is looking for more returns from its most prized IP asset.

Uniloc launched its latest litigation campaign this week in East Texas federal district court, suing 16 defendants including Canon USA Inc., Juniper Networks Inc. and ArcSoft Inc. The complaints, filed on Tuesday, claim the companies infringed Uniloc’s patent for a “system for software registration” by making and selling product registration and activation systems meant to reduce software piracy.

The patent—U.S. Patent Number 5,490,216—is the same one Uniloc asserted against Microsoft, winning a $388 million verdict in April 2009. A judge in Rhode Island tossed the verdict five months later, but the U.S. Court of Appeals for the Federal Circuit upheld the validity of the patent in 2011 and returned the case to the trial court for a new trial on damages. Uniloc and Microsoft reached a confidential settlement the following year.

Uniloc, which holds more than 50 patents, has sued dozens of companies in recent years—not always successfully. Last year it came up short in a case against cloud computing company Rackspace Hosting Inc. when a federal judge in Tyler, Texas, ruled that a different Uniloc patent was invalid. And in March of this year, Uniloc suffered a setback when the same judge gutted its patent claims in another case, derailing a lawsuit against defendant SlickEdit Inc. and possibly others.

As we’ve reported, Uniloc obtained funding from the third-party litigation finance firm Bentham IMF for its cases against Microsoft and others accused of infringing the ’216 patent. The U.S. Patent and Trademark Office recorded last week that Bentham has released Uniloc from a security agreement that gave the funding company rights to the patent.

Uniloc is represented by attorneys at Carter Scholer Arnett Hamada & Mockler in Dallas, as well as by James Etheridge of the Etheridge Law Group and T. John Ward Jr. and J. Wesley Hill of the Ward & Smith Law Firm.