The ruling by the court on Friday was related to one of a series of patent disputes between the two firms as they compete in the market for dynamic random access memory (DRAM) chips, used in personal computers, as well as flat panels.
In the lawsuit filed in May 2002, Matsushita sought $300 million in damages from Samsung, accusing the South Korean company of infringing on three DRAM technology patents.
"The New Jersey federal court in the United States ruled that both Samsung and Matsushita had not infringed on each other's patents," Samsung, the world's largest memory chip maker, told the Korea Exchange in a filing on Monday.
But Matsushita rejected the ruling.
"Samsung violated Matsushita's chip patents, and this ruling is unacceptable," said a spokesman from Matsushita, the world's largest consumer electronics maker. "We are studying necessary measures to overturn this verdict, including a possible appeal."
In January, Japan-based Matsushita sued Samsung in relation to memory chip patents in a U.S. court in Texas, after Samsung filed a similar lawsuit, also in Texas, last September.
Both companies have also been sparring as, used for TVs and computer monitors.
In December, Samsung SDI,and an affiliate of Samsung Electronics, filed suit against Matsushita Electric in a U.S. federal court in Los Angeles, claiming the Japanese firm violated nine patents relating to plasma display panels.