Ivantis Fires Back: It Petitions for Invalidation of the Glaukos iStent® Patent

Last month, it was reported that Glaukos filed a lawsuit against Ivantis, alleging that the Ivantis Hydrus Microstent device infringes on patents held by Glaukos covering its iStent® devices. See “Glaukos Sues Ivantis over patents on iStent® Devices”.

Ivantis has now launched a response: In a filing on May 23, 2018, Ivantis has petitioned the USPTO to invalidate one of the two patents asserted by Glaukos in its lawsuit.

The Petition, which was filed in the USPTO’s Patent Trial and Appeal Board (PTAB), makes use of a procedure known as inter partes review (IPR). The IPR procedure allows those accused of infringement to challenge the validity of a patent based on printed publications and other prior patents.

In this case, Ivantis asserts that the Glaukos microstent patents would have been obvious based in part on a chapter in a German publication: Detlev Spiegel, Chirurgische Glaukomtherapie (translation: “Surgical Glaucoma Therapy”, in Benefits and Risks of Ophthalmological Therapy: Main Presentations of the 33rd Essen Continued Education for Ophthalmologists 79-82 (Herausgegeben von Anselm Kampik & Franz Grehn ed., 1998). The Petition also relies on a prior Australian patent publication and a U.S. patent: Australian Patent Application Publication AU 199876197 (“Grieshaber”); and U.S. Patent No. 5,868,697 (“Richter”).

The Petition itself is included below, and can be downloaded by clicking this link:


According to published PTAB procedures for IPRs, Glaukos is permitted to file a Preliminary Response, after which the PTAB will make an initial determination on whether it will or will not institute an IPR trial. That initial determination usually takes around six (6) months. If it decides not to institute an IPR trial, then that’s the end of it in the USPTO. On the other hand, if it decides to institute an IPR trial, then the PTAB will determine whether it will or will not invalidate the patent, with a final written decision typically issuing around one (1) year after institution.