History (1995): US Court Invalidates Rodime Patent on 3.5-Inch HDDs

Quantum (Milpitas, CA) announced that the U.S. Court of Appeal has upheld the ruling of the U.S. District Court for the District of Minnesota in April of 1994, which found in favor of Quantum’s motion for summary judgment over a patent dispute with Rodime PLC (Glasgow, Scotland).

Both courts have declared invalid certain claims of Rodime’s U.S. patent No. 4,638,383 covering HDDs using 3.5-inch disks and a head-positioning mechanism which consists of a rotary actuator driven by an open loop-stepper motor.

The patent declaratory lawsuit was first filed by Quantum against Rodime in March 1993.

“Our diligence has resulted in a ruling that represents a significant victory not only for Quantum but for the entire disk drive industry,” said the US company.

Founded in 1980, the Scottish firm which devised the 3.5-inch form factor for HDDs in 1983 halted all production at the end of 1990 in order to devote itself full time to a single activity: drawing income from its patents.

Legal battles were then initiated against almost all manufacturers of HDDs. Among the firms who lost their suits or agreed to royalty payments (at times in excess of $10 million) are IBM, Alps, MiniScribe/Maxtor, Conner, Fujitsu, Hitachi and Matsushita.

This article is an abstract of news published on the former paper version of Computer Data Storage Newsletter on issue ≠93, published on October 1995.