SAN DIEGO—The U.S. Patent and Trademark Office (USPTO) has issued a notice in the re-examination of Zeiss’ 6,089,713 (’713) patent on June 10, 2014 confirming that the patent’s eight original claims were patentable. The USPTO also ruled that 15 additional claims submitted by Zeiss were patentable.

The request for a re-examination of the ’713 patent was filed by Ocuco Inc. on October 4, 2013. The USPTO rejected Ocuco’s challenges to the validity of the ’713 patent, and in so doing confirmed its strength. The panel of three patent examiners found all of Zeiss’ arguments distinguishing the prior art to be persuasive.

The ’713 patent covers certain types of back-surface free-form progressive lenses and processes by which they are made. These include types of progressive lenses whose front surfaces are rotationally symmetric with the back-surface progressive design determined by the individual prescriptions alone or in combination with other customization options.

“We are pleased the USPTO has found all of the original ’713 patent claims patentable and also granted 15 new claims,” said Karen Roberts, Zeiss’ vice president of customer enablement. “These new claims provide specificity regarding the optimization of lenses for vertex distance, binocular vision, frame form and frame fit. This increases the protection for our business and for the businesses of our many licensees.”

On Feb. 19, the U.S. Patent and Trademark Office, in a similar move, terminated a re-examination of Seiko Epson’s patent 6,019,470 that was requested by Ocuco. As VMail reported, the USPTO confirmed all of the patent’s 20 original claims, and ruled that six additional claims submitted by Seiko are confirmed and patentable. Seiko Epson’s ’470 patent, issued on Feb. 1, 2000, covers the invention of back-surface progressive lenses.

In 2012, Zeiss prevailed over rival lens manufacturer Signet Armorlite in a lengthy lawsuit concerning the ’713 patent.