Ordinarily patent practitioners do not need to really think about prosecution laches, but laches has become a rather hot topic as the United States Patent and Trademark Office and courts have initiated what can only be characterized as an assault on an applicant’s statutory right to seek and file additional claims if those claims are supported by the initial disclosure. 

Prosecution laches is only supposed to apply in egregious cases of unreasonable and unexplained delay in prosecution. And a finding of prosecution laches is supposed to require that the accused infringer suffered prejudice as a result of egregious applicant delay by proving investment in, work on, or use of the claimed technology during the period of delay. Last year the Federal Circuit ignored the requirement of prejudice when it found that PMC engaged in egregious and unreasonable delay, which result in a finding of laches in Apple's favor despite the fact that Apple did not even start any infringing activity until years after the delay ended.

Join Gene Quinn, President & Founder of IPWatchdog, Dean Geibel, Chief Patent Counsel for Samtec, and Eric Foster, Intellectual Property Counsel for First Solar. 

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