Mentor Graphics

(MENT)

will pay

Cadence Design

(CDN)

$18 million to settle patent litigation over technology used to map circuitry on semiconductors.

Mentor closed Monday at $19.49, just shy of its 52-week high and up 148% for the year. Cadence closed Monday at $13.82, also near its 52-week high and up 19% for the year.

Mentor and Cadence both sell software used to design semiconductors. The two companies and their subsidiaries have been suing each other for years over the patents, which cover a chip manufacturing procedure known as "emulation." Cadence's Quickturn unit had recently won an injunction that prevented Mentor from selling a line of emulators in the U.S.

As part of the agreement, the two companies have agreed not sue each other over this type of technology for seven years.