A tale of two outcomes: what SecureWave Storage case studies reveal about prior art

It is legally and financially beneficial for a defendant in a patent infringement dispute to utilise the inter partes review process to attempt to invalidate asserted patent claims. Given the popularity of this process, the associated practice of law in petitioning these reviews before the PTAB has become fairly specialised. Industry focus, case selection and, of course, legal expertise and experience from one firm to the next play key factors. Often overlooked is the quality and methodology of obtaining the prior art that is central to any inter partes review argument. This article reviews Global Prior Art’s internal database of over 17,000 invalidity prior art cases addressed since the firm was created in 1982, including many thousands in which Global Prior Art supported subsequently filed inter partes review petitions, to pinpoint case studies that illustrate the impact of strong (and weak) prior art and the underlying methodologies used to obtain them. The learnings from these case studies – which will be presented over the next few weeks in the IAM weekly newsletter – can be instrumental in setting out strong arguments for inter partes reviews and, in turn, increasing an attorney’s likelihood of success.

Case study three – Kingston Technology v SecureWave Storage and Unified Patents v SecureWave Storage

Kingston Technology Company, Inc v SecureWave Storage Solutions Inc (IPR2019-00494) and Unified Patents LLC v SecureWave Storage Solutions Inc (IPR2019-00501) highlight the critical importance of a thorough, comprehensive prior art search and how a patent attorney’s hand is shaped by their perception of the available prior art.

As a pair, the cases contrast the results of an inter partes review filed previously using prior art from a search that appeared to rely principally on keyword matching and the references uncovered by a technical expert who relied on a detailed, manual review of prior art documents. 

Another important aspect was the close interaction with the client, since claim construction for contested limitations was a key issue and the client’s guidance on construction of the claim terms was an important prior art search focus. In addition, the obviousness to combine the uncovered references with the previously known art was contested, with the PTAB concluding that the petitioner had articulated sufficient reasoning “to support the legal conclusion that its preferred combination would have been obvious to one skilled in the art” (see page 12 of IPR2019-00501 final written decision).

US Patent 7,036,020 (the ‘020 patent) relates to secure external storage technology and was asserted by SecureWave Storage Solutions Inc against Kingston Technology Company, Inc and Micron Technology, Inc in 2018 in the US District Court for the District of Delaware (1:18-cv-01398 (DDE)). The patent was challenged by two unrelated inter partes reviews, coincidentally filed only a week apart in late 2018. Both inter partes reviews put forth arguments primarily relying on US patent publications for prior art evidence; however, they yielded dramatically different outcomes.

The first inter partes review, IPR2019-00494, was filed by Kingston and was denied institution on the merits on all 14 challenged claims. A close review of the cited prior art strongly suggests that a search deploying keywords and phrases was utilised as the principal search strategy.

In contrast, IPR2019-00501, was filed by Unified Patents and prevailed in obtaining a final written decision invalidating all five challenged claimed. In this case, Unified relied on two key prior art references (US 5,623,637 to Jones and US 6,931,503 to Robb). Interestingly, these two references identified by Global Prior Art’s team use different terminology than the asserted patent to describe a similar data security implementation. These references could only have been found through a detailed and manual review of key sub-classes germane to this technology as performed by an experienced searcher. 


For a prior art search to be truly comprehensive, keyword searching may be necessary but is insufficient. Manual searching of the patents within relevant sub-classes by a technical specialist is necessary in order to improve the likelihood of discovering references that may utilise terminology different from the target patent and thus missed by keywords and key phrases.  

In addition, close interaction between the attorney and prior art team is essential to transfer knowledge regarding contest limitations shaping claim construction.

This is an Insight article, written by a selected partner as part of IAM's co-published content. Read more on Insight

Unlock unlimited access to all IAM content