The boss of Sun Microsystems used his blog to dispute Network Appliance’s charge that Sun’s ZFS file system technology infringes on seven NetApp patents.

NetApp made the charges in a lawsuit filed in a Texas federal court.

In his blog, CEO Jonathan Schwartz also challenged NetApp’s contention that Sun had sought licensing fees for the storage firm’s use of WAFL (Write Anywhere File Layout) or other technologies. Instead, he said that NetApp contacted Storage Technology before Sun acquired it in 2005 through a third-party "intermediary," seeking to discuss acquiring undisclosed patents on storage technology.

He did not elaborate on the state or details of those talks in the blog.

Following the acquisition, Schwartz said Sun decided not to sell the patents, but would provide the technologies sought by NetApp under licensing agreements. He noted that NetApp was not interested in licensing the technology.

"Instead of engaging in licensing discussions, NetApp decided to file a suit to invalidate them," Schwartz wrote in his blog. "To be clear, we never filed a complaint or threatened to do so, nor did anyone, to the best of my knowledge, in the ZFS community."

In a statement, Sun said that the lawsuit is proof that NetApp views the open-source ZFS technology as a competitive threat. The company also said the lawsuit is a "direct attack on the open-source community."

Analysts have said that the lawsuit could become a test case for open-source software.

Said Schwartz in his blog: “The rise of the open-source community cannot be stifled by proprietary vendors. I guess not everyone’s learned that lesson.”

Read the background and analysis on this story by Chris Mellor here, and on his blog.