In what is shaping up to be a nasty spat, Sun has counter-sued start-up GreenBytes. The server company has reponded to GreenBytes' claims that its data de-duplication technology had been stolen by Sun.

Sun said GreenBytes, which was founded in 2007 and appears to be still in stealth mode, claimed to have developed proprietary source code called ZFS+ for use with Sun's ZFS (Zettabyte File System) technology. ZFS is open source, but GreenBytes told Sun it did not intend to make its code open source, according to a lawsuit Sun filed last month.

The complaint, which Sun filed in the US District Court for the Northern District of California on 19 June and amended on 6 July, tells a tale of a relationship gone sour between a legendary Silicon Valley company and an innovative Rhode Island startup. The fact that Sun is in the process of being acquired by Oracle adds a further twist to the tale.

GreenBytes claimed it had software that can cut storage power consumption by half. That software includes data de-duplication, a popular technology for reducing storage requirements by eliminating redundant data. The company obtained a Common Development and Distribution License (CDDL) from Sun to access and use the source code of Sun's OpenSolaris and ZFS software, and entered into a non-disclosure agreement (NDA) that allowed it to buy Sun equipment and add its own technology for sale to end-users, according to Sun.

A GreenBytes white paper still hosted on Sun's Internet domain describes ZFS+ and the Cypress NAS Filer appliance, a hardware platform based on the Sun X4500 server platform. "At GreenBytes we start with ZFS and make it better by adding a set of compelling technologies design (sic) to increase storage efficiency and dramatically reduce TCO (total cost of ownership)," the white paper said.

But in its complaint, Sun said GreenBytes courted the larger company and then turned on it.

"By its own admission, GreenBytes has been trying to entice Sun to acquire GreenBytes or to become an investor," the complaint said. "GreenBytes invited Sun to review GreenBytes' claimed de-duplication process pursuant to the parties' NDA. When Sun ultimately rejected GreenBytes' overtures, GreenBytes responded by making groundless claims that Sun had misappropriated GreenBytes' deduplication process."

GreenBytes then demanded the company turn over "vast amounts of information" about Sun's development of its de-duplication process, the complaint said. GreenBytes also accused Sun of violating the Computer Fraud and Abuse Act, Sun said. That federal law covers unauthorised use of a computer or data from a computer, among other things.

Sun wants a declaratory judgment that it is the rightful owner of its de-duplication technology and that GreenBytes' accusations aren't true. It also wants to keep GreenBytes from "interfering with Sun's disclosure of its de-duplication process to Oracle or other third parties." Sun is also seeking injunctive relief and damages.

In addition, Sun said GreenBytes used the ZFS trademark without Sun's authorisation and fraudulently obtained a trademark on the name ZFS+. This causes confusion that "there is an association between Sun and GreenBytes," Sun wrote.

Sun officials declined to comment on pending litigation. GreenBytes could not be reached for comment.

If GreenBytes is trying to claim ownership of technology built on top of an open-source platform such as ZFS, it may be in a tough position, said Illuminati analyst John Webster.

In addition, Sun could have licensed the de-duplication technology from any of multiple vendors, Webster said. For example, Hewlett-Packard has an OEM arrangement with Sepaton.

"I don't see that they would have had to ... rip off somebody in order to get it," Webster said.