"The second one, No. 5,412,717, is also credited to Fischer and was granted in May 1995. The invention deals with using hashes — unique numerical identifiers — to ensure an application has not been tampered with. IPAT is asking for a jury trial in U.S. District Court for the Eastern District of Texas, where many companies choose to file patent disputes. IPAT seeks an injunction against the companies using the technologies and damages. Also named in the suit are companies AVG, Check Point Software, Comodo, ESET, F-Secure, Iolo technologies, Kaspersky Lab, McAfee, MicroWorld Technologies, NetVeda, Norman Data Defense Systems, Novell, PC Tools, PWI, Sophos, Sunbelt Software, Trend Micro, Velocity Micro and Webroot Software."