Fujitsu has filed a patent infringement lawsuit against Taiwanese memory chip maker Nanya over DRAM.

The lawsuit was filed in the Tokyo District Court this morning and seeks a court order prohibiting the future importation and sale of products that Fujitsu says infringe on its patent. Fujitsu is also asking the court to award it monetary damages, although it has refused to comment on the amount being sought.

The suit covers a patent related to a technology for improving the speed of DDR SDRAM memory chips. It was filed after talks between the two companies failed to produce an agreement on patent licensing.

In a statement, the company said that it had "determined that litigation was necessary in order to protect the value of its intellectual property in the DRAM area".

Head of the company's intellectual property arm, Masanobu Katoh, said: "Fujitsu has been conducting research and development of semi-conductors for years and owns over ten thousand patents around the world in the field of electronics devices, including semi-conductor memories. We consider our intellectual properties as important company assets and believe it is our right to pursue their protection under international rules."