On December 31, 2001, MIPS announced that it was dropping its patent-infringement lawsuit against Lexra as part of an agreement between the two companies. As part of this agreement, Lexra will assign its processor IP assets to MIPS and become a MIPS32 licensee. This announcement spells the end of Lexra's DSP-enhanced licensable core: Lexra is exiting the IP business and becoming a fabless semiconductor company focused on network processors.
In its lawsuit, filed in November 1999, MIPS alleged that Lexra has violated at least two and as many as eleven MIPS patents. One of the patents covers a method for preserving precision in the single-instruction multiple data (SIMD) operations in MIPS' MDMX multimedia extensions. MIPS alleged that the SIMD operations in Lexra's DSP-oriented Radiax instruction set extensions violated this patent.
Ironically, while the MDMX extensions have been largely ignored, Lexra claimed 11 licensees for its Radiax-enhanced cores. Now that MIPS owns Lexra's processor IP, will MIPS adopt the Radiax DSP extensions for its own use? MIPS certainly has strong motivation to revisit its DSP strategy; competitors like ARM and Hitachi are gaining wide acceptance of their DSP-enhanced processors, leaving MIPS to play catch-up.
Lexra is not the only core licensor to exit the IP business recently. Last February, Massana dropped its IP offerings and repositioned itself as a fabless chip company. In December, picoTurbo announced that it was exiting the IP business as part of a settlement with ARM. As in the Lexra/MIPS settlement, picoTurbo will cease business as an IP vendor and relinquish its IP assets to ARM (unlike Lexra and Massana, it appears that picoTurbo does not have a fall-back position and is closing its doors). The number of core vendors has exploded in recent years; the Lexra and picoTurbo settlements may signal the start of a significant contraction in the ranks of core vendors. It is quite possible that other core vendors will go the way of Lexra, Massana, and picoTurbo before this cycle ends.