Seven Chinese neodymium iron boron magnet producers have come together to end the patent monopoly held by Japanese companies in the rare-earth magnet sector.

The alliance, led by Shenyang General Magnetic Co Ltd, is set to challenge Japanese companies like Hitachi Metals Ltd, which had the intellectual property patent rights for neodymium iron boron till July 8.

Sun Baoyu, chairman of the board of Shenyang General Magnetic Co Ltd, said the companies have set aside $15 million for legal expenses that may arise due to lawsuits that may be filed by the Japanese companies.