    Sentence 1: The Infineon cose began in August 2000 ,  when Rombus accused Infineon of patent infringement  ond Infineon counter-sued Rombus for breach of contract  ‘ond froud .   Sentence 2: At thot time , Rombus accused Infineon of  potent infringement and Infineon countersued Rambus  for breach of contract ond fraud.