IPR Estoppel Does Not Bar Commission Investigative Staff from Asserting Prior Art References in an ITC Investigation

Oct 15, 2018

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The estoppel provision of 35 U.S.C. § 315(e)(2) prohibits the “petitioner . . .[,] real party in interest or privy of the petitioner” from raising grounds of invalidity that were “raised or reasonably could have [been] raised, during [IPR]” in a district court litigation or an investigation before the ITC.   

Prior to the instant ITC investigation, respondent Fujifilm had petitioned for IPR of one of Sony’s patents. The PTAB instituted review of the patent, but determined (in its final written decision) that it was not unpatentable. In the ITC investigation, Sony asserted the same patent against Fujifilm and contended that Fujifilm was estopped from relying on prior art references asserted in the IPR.

Sony also went one step further by arguing that the Commission Investigative Staff were estopped from asserting Fujifilm’s IPR references. In response, the Staff argued that 35 U.S.C. § 315(e)(2) “only estops the petitioner in an inter partes review,” and further that it was not a petitioner or even a party to the IPR. The ALJ found the Staff’s argument persuasive and held that “Regardless of whether 35 U.S.C. § 315(e)(2) estops Fujifilm, as contended by Sony, the statute does not prevent Staff from raising the references in this investigation, which it did.”  With the estoppel issue resolved, ALJ Cheney addressed the prior art references and found the asserted claims of the Sony patent invalid for anticipation and obviousness.  

Practice Tip:  Patent owners should be cognizant that, in ITC investigations, the estoppel provision of 35 U.S.C. § 315(e)(2) has been interpreted as being strictly limited to the petitioner, the real parties-in-interest or privies of the petitioner—but not encompassing the Commission Investigative Staff. This leaves open the possibility of the Staff raising invalidity challenges that have been previously rejected by the PTAB.

In the Matter of Certain Magnetic Tape Cartridges and Components Thereof, 337-TA-1058 (ITC October 2, 2018, Order) (Cheney, ALJ).

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