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U.S. Silica Defends Patents

U.S. Silica Holdings Inc. announced that the United States Patent and Trademark Office has confirmed several additional patent claims covering fundamental aspects of technology owned by its SandBox Logistics business unit, continuing to validate the strength of the SandBox patent portfolio.

These wins mean that Proppant Express Investments LLC (PropX) is judicially barred from making the same or similar invalidity arguments in any future infringement proceedings involving these patents,” according to U.S. Silica.

"We are very pleased that the SandBox patent portfolio continues to hold up so well against challenges from PropX,'' said Bryan Shinn, U.S. Silica president and chief executive officer. ''We've now seen the Patent Office uphold key claims in three of the four IPRs initiated by PropX, including claims central to our underlying infringement action against PropX. Our success rate in these IPRs is well above the statistical norm and positions us extremely well in our ongoing action against PropX.''