Data storage makers duke it out. (Up front: news, trends & analysis).

At one time, Hewlett-Packard (HP) and information storage company EMC were sales partners, but since the 1990s, the two data storage makers have been bitter competitors. And their escalating battle is keeping plenty of lawyers in business.

In October, EMC and HP exchanged patent infringement suits. In a lawsuit filed in U.S. District Court in San Jose, Calif., HP stated that three of EMC's product lines contained technology that violated seven of HP's patents. HP is seeking unspecified monetary damage and has asked the court to block distribution of EMC's Symmetrix and Clarion hardware lines, as well as its Timefinder software. EMC subsequently filed its own patent infringement complaint against HP in U.S. District Court in Worcester, Massachusetts., alleging that certain HP products infringe six patents owned by EMC for Symmetrix, TimeFinder, and two other products.

Despite their once-amicable relationship, the bad blood between the two companies extends beyond the recent lawsuits. EMC previously sued StorageApps of New Jersey, a company that was later purchased by HP that once employed former EMC executives. In addition, EMC and HP ally Hitachi Data Systems are suing each other for patent violation claims related to data storage software.

As a result of its merger with Compaq Computer, HP moved past EMC and became the biggest provider in the external storage market. As recently as July, however, the companies agreed to cooperate and share certain source code for data storage software--an important step as the industry attempts to create standards to enable hardware from various vendors to work together. But the recent suits have all but killed any collaboration efforts. Regardless of who wins the court battles, the real loser will most likely be the data storage software industry.