The U.S. Court of Appeals for the Federal Circuit sent a patent dispute between American Medical Systems Holdings Inc. and Biolitec AG back to district court.
American Medical had sued Biolitec in 2007, claiming that company's Evolve SLV laser system infringed on patents for devices used in laser therapy for an enlarged prostate. American Medical makes a range of products used for vaporization of tissue using laser technology.
The U.S. District Court for the District of Massachusetts decided in 2009 that Biolitec's device did not perform "photoselective vaporization of tissue," and therefore did not infringe on American Medical's patents.
In its ruling on Monday, the appeals court rejected the district court's decision, citing problems with the initial decision's definition of the term "photoselective" and its relation to the range of laser wavelengths used in treatment.
The case now goes back to the district court.
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