Tandon, which has accused some of its Japanese competitors of patent infringement, is being sued itself on charges that it pirated disk drive technology.
The suit against the Chatsworth-based computer equipment company and its chairman, Sirjang L. (Jugi) Tandon, was filed last week in Los Angeles federal court by Sanders Associates and Billings Computer. The plaintiffs allege that the technology for Tandon's double-sided, floppy disk drive was invented by employees of California Computer Products.
California Computer Products, now part of Sanders Associates, sold its floppy disk drive operation to Billings in 1979.
Tandon said the suit is "without merit." The company said its patent for the disk drives at issue is 9 years old. When Sony raised the issue at an International Trade Commission hearing last year, Tandon said, the panel rejected the argument that Sanders and Billings should own the patent.
The same patent is central to a similar complaint Tandon lodged with the commission against Sony, Teac and Mitsubishi. Sony and Teac subsequently reached settlements with Tandon. The commission later ruled, however, that Mitsubishi did not infringe on Tandon's patent.