PathScale Inc. is a company that develops a highly optimizing compiler for the x86-64 microprocessor architectures. It derives from the SGI compilers for the MIPS R10000 processor, called MIPSPro. PathScale was originally founded in 2001 as Key Research and its original mission was to develop clustered Linux server solutions based on a low-cost 64-bit design. In late 2003 the company came out of stealth mode and was called PathScale.