DEC Alpha

14 operating systems

Operating system	Developer	First release	License
FreeBSD	—	1993	2-clause BSD License
Gentoo Linux	—	—	GNU General Public License
Microsoft Windows	Microsoft	1985	proprietary license
NetBSD	—	1993	BSD licenses
OpenBSD	OpenBSD Project, Theo de Raadt	—	ISC license
OpenVMS	VMS Software Inc., Hewlett-Packard, Digital Equipment Corporation, Compaq	1977	proprietary license
Plan 9	Bell Labs	1992	GNU General Public License, version 2.0, MIT License, Lucent Public License
Red Hat Linux	Red Hat	1994	GNU General Public License
Tru64 UNIX	Hewlett-Packard, Digital Equipment Corporation, IBM, Compaq	—	proprietary license
Windows 2000	Microsoft	2000	proprietary license
Windows NT	Microsoft	1993	—
Windows NT 3.5	Microsoft	—	commercial software, proprietary license
Windows NT 3.51	Microsoft	1995	proprietary license
Windows Server 2000	Microsoft	2000	—