Intellectual Ventures has settled a lawsuit it brought against chipmaker Altera Corp, according to court filings in litigation against a group of semiconductor companies filed by the firm, which has purchased billions of dollars worth of patents.

Intellectual Ventures sued Altera for patent infringement in December 2010 in a case that eventually included three other chipmaker defendants. According to documents filed this week in a Delaware federal court, Altera and Intellectual Ventures agreed to dismiss all claims against each other.

Terms of the deal, including any potential patent licenses, were not disclosed in the filings. IV had previously announced settlements with Lattice Semiconductor Corp and Microsemi Corp. The sole remaining defendant in the case, Xilinx, is also an IV investor, according to court documents. 

Representatives for IV, Altera and Xilinx could not immediately comment on Friday.

IV, founded in 2000, has raised about $6 billion from investors and says it creates an organized mechanism for innovators to capitalize on their ideas. However, critics in the technology industry say patent litigation and royalty payments have become a burdensome tax on innovation, and that firms like IV that do not primarily make products are taking advantage of the system.

In October, sources told Reuters that Intellectual Ventures had curtailed its patent buying while it tried to raise $3 billion more. They said the company had pushed back the closing dates on some patent deals and bowed out of others.

Earlier this month, the U.S. House of Representatives passed a bill aimed at making it harder for patent assertion entities to file lawsuits.

Democratic Senator Patrick Leahy of Vermont, chair of the Judiciary Committee, and Senator Mike Lee, a Republican from Utah, have also introduced a similar bill. A Senate hearing on the issue is scheduled for next week.

The case in U.S. District Court, District of Delaware is Intellectual Ventures I LLC and Intellectual Ventures II LLC vs. Altera Corp et al., 10-1065.