Network Appliance is suing Sun Microsystems over the ownership of Sun's ZFS data-processing technology.
Network Appliance said, "In the wake of prolonged and aggressive claims by Sun Microsystems against the company, we have filed suit seeking a declaration that Network Appliance is not infringing three of Sun's US patents, and that those patents are invalid."
The suit also seeks a ruling that Sun infringes seven NetApp US patents, covering data-processing systems and related software. The suit is particularly targeted at Sun's ZFS technology.
NetApp said, "Sun's aggressive demand that we license some of their intellectual property caused us to examine carefully whether we were infringing their intellectual property rights and whether they might be infringing ours."
NetApp is seeking damages against Sun and an order for its rival to stop the alleged distribution of patented NetApp technology to customers.