Litigation
Several successful litigations show that software patents are enforceable in the US. See List of software patents for more examples.
Similarly in Japan, software patents have been successfully enforced. In 2005, for example, Matsushita won a court order barring Justsystem from infringing Matsushita's Japanese patent 2,803,236 covering word processing software. A Tokyo court ordered Justsystem to pull their product from the market. On September 30, 2005, Intellectual Property High Court of Japan, which was established in April 2005, granted Justsystems' appeal and overturned the Tokyo District Court decision in October 2005.
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