OASIS was founded under the name “SGML Open” in 1993. It began as a consortium of vendors and users devoted to developing guidelines for interoperability among products that support the Standard Generalized Markup Language (SGML). The consortium changed its name to “OASIS” (Organization for the Advancement of Structured Information Standards) in 1998 to reflect an expanded scope of technical work.
Also see: SGML Open – Why SGML & Why a Consortium?