IBM, Oracle, SAP and Adobe Systems are being sued for the alleged infringement of software patents.
Bloomberg reports that Implicit Networks says the organisations are violating two patents that let the server software speed up its security functions.
Apparently, the patents were issued in 1998 and 2001.
Impicit Networks isn't asking them to stop using what it claims is its technology, but it looking to receive a royalty payment instead.
The products involved are WebSphere from IBM, Oracle's application server, WebLogic from BEA (part of Oracle), NetWeaver from SAP, and both JRun and ColdFusion from Adobe.