Memristor Patent ReExams and Prior Art

In the past few years there has been increasing interest in the resistance switching properties of nanoscale thin films to develop a new form of non-volatile memory called ReRAM. This interest was peaked in 2008 based upon a paper published in Nature by researchers from HPLabs which connected experimentally observed resistance switching of TiO2 thin films to a memristor model postulated in the 1970's by Leon Chua and Steve Kang. Companies including HP, Sharp, Unity Semiconductor, and Adestos Technology are projecting product release of different variations of ReRAM/memristor in the 2-3 year timeframe.

There are actually several material examples of memristive materials dating back to the the 1960's such as discussed by the article "Switching Phenomena in Titanium Oxide Thin Films," by Argall. However, some of the companies which have been patenting around the concept of ReRAM and memristors have not adequately considered the prior art. Over the past year I have taken a look at several of the companies and patents related to memristors and ReRAM and have begun to compile information on patents which appear to have issued without considering prior art relevant to 35 USC 102 (novelty) or 35 USC 103 (obviousness). In some extreme cases I have filed Ex Parte ReExams for patents which clearly fail to meet patentability standards.

A copy of the Ex Parte ReExam filings as well as copies of filings of prior art under 37 CFR 1.501 is available at this link. A discussion of the business landscape of memristive electronics is available here.