Rambus beat Hynix in its patent infringement case and a court ordered Hynix to pay $306 million in damages.
The court upheld all 10 of Rambus' patent claims, said a representative for the company.
The memory designer alleged that Hynix and other large memory manufacturers infringed its patents when making DDR DRAM, the most common type of memory in PCs today. Those memory makers denied this, but have not been winning the argument in court.
Rambus is actively litigating other suits against other memory manufacturers.