Intergraph said the patented PIC technology is an essential component in Texas Instruments' TMS320C6000 family of digital signal processors (DSP).
The Texas Instruments DSPs were not developed until 1997. Intergraph had developed PIC in the early 1990s for use in its C5 Clipper line of microprocessors.
In October last year, a judge ruled that Intergraph's patents were valid and enforceable during a lawsuit that Intergraph had filed against Intel over its Itanium processor line.
In December 2002, Intergraph sued Dell Computer, Hewlett-Packard and Gateway for infringing its Clipper memory management patents.