The Scieneer CL is developed by Douglas Crosher at Scieneer and is a commercial fork of the CMU Common Lisp implementation. Douglas contributed to the CMUCL for many years before creating the Scieneer CL fork of CMUCL. The Scieneer CL 1.1 was publicly released in September 2002. The Scieneer CL 1.2 version was released in September 2003 and was the first Common Lisp implementation for the 64-bit AMD64 platform. The Scieneer CL 1.3 version was released in April 2006 and added support for Solaris on x86 and 64 bit AMD64 platforms. The Scieneer CL was made available free for non-commercial use in October 2008.