Toshiba has filed patent infringement lawsuits in Japan and the US against South Korea's Hynix Semiconductor.
The suits allege that Hynix violated Toshiba's patents covering NAND-type flash memory chips. The Japanese company is seeking damages and a halt to sales of the products that allegedly infringe its patents.
Both lawsuits relate to a patent cross-licensing agreement signed between Toshiba and Hynix in 1996. Toshiba said the agreement expired two years ago and the companies had been unable to agree on a revision of the arrangement.
Kim Soo-Kyoum of market research company IDC said the suits accompanied legal moves last month by Toshiba's flash memory development and production partner SanDisk against STMicroelectronics, which partners Hynix in making flash chips.
Flash memory has the ability to maintain its contents even after power to the chip has been turned off. This has made it one of the most commonly used types of memory chip in devices such as consumer electronics products, mobile phones and digital music players. DRAM is the most commonly used type of memory in personal computers.
Toshiba is the world's second biggest NAND flash memory maker with about 34% of the market, according to IDC. Kim said Hynix, which started volume production of NAND flash only recently, had a very small share.
If the lawsuit forces Hynix to pay royalties, Toshiba will benefit from any success Hynix and STMicroelectronics have in the market.
"It's a win-win situation for Toshiba," Kim said.
An industry insider said that Toshiba was also concerned that the increase in flash memory production by Hynix and STMicroelectronics might further erode already falling prices, cutting into Toshiba and SanDisk profits.
Paul Kallender and Martyn Williams write for IDG News Service