There is no legal duty to investigate whether a competitor has patents. In fact, some lawyers suggest that it may be better not to search for competitors’ patents, because of the possible problems that can occur once you learn of the existence of a problematic patent.
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The patent laws authorize a court to increase the damages in patent infringement lawsuits up to three times the amount found or assessed. This is known as the “treble damages” award. A decision to increase damages is discretionary with the court, but is usually exercised only in cases of willful and wanton infringement or bad faith litigation. Fortunately, an increase in damages is inappropriate when an infringer mounts a good faith and substantial challenge to the validity of the patent or the existence of infringement.