Informix was established by Laura King and Roger Sippl, under the name Relational Database Systems Inc in 1980. In 1988 the company changed its name to Informix Software Inc.
The Informix DBMS started from the Ingres system that also led to Sybase and Microsoft SQL Server. During the 1990s Informix was the second most popular database, after Oracle.
Informix was aquired by IBM in 2001. IBM has merged some of the technologies used in Informix database into DB2. IBM continues the Informix product line as independent product too.