* Rambus says U.S. patent office ruling was in error

* Rambus says IBM application infringes 2002 patent

* IBM says patent office ruling was correct (Adds IBM comment)

NEW YORK, Aug 24 (Reuters) - Chip designer Rambus Inc (RMBS.O) has sued International Business Machines Corp (IBM.N), seeking to reverse a federal agency finding that Rambus' patent for a memory system was not infringed.

In a lawsuit filed Monday in federal court in San Jose, California, Rambus said the U.S. Patent and Trademark Office erred through a series of decisions in finding that a patent application assigned to IBM did not interfere with a Rambus patent obtained at the end of 2002.

According to a June 24 ruling by the office's Board of Patent Appeals and Interferences, the patent concerns a memory controller that communicates to at least one memory subsystem, with an independent point-to-point link used between the controller and each subsystem.

"The board committed errors of fact and law in its orders, decisions, and judgment," Rambus said in its complaint.