This article needs additional citations for verification. (November 2019)
|Founder||Dr. Peter A. Alsberg|
Addamax was an American software company that developed Trusted operating systems based on UNIX System V and Berkeley Software Distribution (BSD) variants of UNIX. The company was founded in 1986 in Champaign, Illinois by Dr. Peter A. Alsberg and had a sales and development office in Gaithersburg, Maryland.
Addamax filed a high-profile antitrust lawsuit in 1991 against the Open Software Foundation (OSF), alleging that OSF created a cartel that controlled the UNIX operating system and exerted monopsony price fixing and led to the company going out of business.
- Wong, R. M. (1990). "A comparison of secure UNIX operating systems".  Proceedings of the Sixth Annual Computer Security Applications Conference. Institute of Electrical and Electronics Engineers. pp. 322–333. doi:10.1109/CSAC.1990.143794. ISBN 0-8186-2105-2. S2CID 21640545.
- "Addamax Corp. v Open Software Foundation, Digital Equipment Corporation and Hewlett-Packard Company". GTW. Archived from the original on January 6, 2009. Retrieved March 11, 2012.
- "U.S. 1st Circuit Court of Appeals: ADDAMAX CORPORATION v OPEN SOFTWARE". FindLaw. September 4, 1998. Retrieved March 11, 2012.