IP Law Daily Double-patenting challenge to non-volatile memory patent could not be resolved summarily
Thursday, April 27, 2017

Double-patenting challenge to non-volatile memory patent could not be resolved summarily

It could not be determined on summary judgment whether a patent for non-volatile memory devices was invalid because of obviousness-type double patenting, the federal district court in San Francisco has decided. There was conflicting evidence as to whether the challenged patent was patentably indistinct or obvious in view of two related patents. The challenged patent did not qualify for a safe harbor from obviousness-type double patenting invalidity provided by 35 U.S.C. §121 with regard to divisional applications filed as a result of a restriction requirement, the court also held. The challenged patent issued from a continuation-in-part application, rather than a divisional application, and it claimed the same invention as a restricted ancestor patent (MLC Intellectual Property, LLC v. Micron Technology, Inc., April 26, 2017, Illston, S.).

MLC Intellectual Property, LLC, alleged that Micron Technology, Inc., infringed U.S. Patent No. 5,764,571 ("the ’571 patent"), titled "Electrically Alterable Non-Volatile Memory with n-bits Per Cell," by making, selling, and importing over 150 different products. The ’571 patent disclosed non-volatile memory devices and methods of programming and/or verifying the programming of multi-level non-volatile memory devices. Non-volatile memory is capable of retaining the data with which it is programmed after the device is powered off.

MLC held two related patents, U.S. Patent No. 7,911,851 ("the ’851 patent") and U.S. Patent No. 8570,814 ("the ’814 patent"), both titled "Memory Apparatus Including Programmable Non-Volatile Multi-Bit Memory Cell, and Apparatus and Method for Demarcating Memory States of the Cell." Both of those patents related generally to non-volatile memory devices, and more specifically to apparatus and methods involving memory-state demarcation and programming reference signal generation in multi-level non-volatile memory devices.

Micron asserted that the ’571 patent was invalid because of obviousness-type double patenting in view of either the ’851 or ’814 patent. Obviousness-type double patenting prohibits an inventor from extending his right to exclude through claims in a later-expiring patent that are not patentably distinct from the claims of the inventor’s earlier-expiring patent. This doctrine applies where two patents that claim the same invention have different expiration dates. MLC sought a declaration that the ’571 patent is not invalid because the safe harbor provided by 35 U.S.C. §121 applied. Both parties moved for summary judgment.

Safe harbor. The Section 121 safe harbor protects certain patents and patent applications from double patenting rejections/invalidations when the USPTO has issued a restriction requirement. A restriction requirement may be issued when an application claims two or more independent and distinct inventions; the applicant will be required to choose one of the inventions for prosecution and can file one or more divisional applications claiming the non-elected inventions. Section 121 is intended to protect an applicant from losing rights when an application is divided. The safe harbor only applies when: (1) the divisional application was filed "as a result" of the restriction requirement and (2) the divisional application did not contain claims drawn to the invention chosen for prosecution in the parent application (referred to as the "consonance" requirement).

MLC argued that the safe harbor applied because the ancestor application that ultimately led to all three patents was subject to a formal restriction requirement, and in response to that restriction requirement, MLC filed a divisional application. But for the restriction requirement, Micron contended, it could have pursued all of the ’571/’851/’814 patents’ claims in a single application. Micron also argued that the consonance requirement was met because the ’571 and ’851/’814 patents were directed toward different inventions identified in the ancestral application’s restriction requirement.

The court disagreed with MLC’s contention that consonance only required that the challenged ’571 patent and the reference ’851/’814 patents be directed toward different inventions. In this case, consonance required that the challenged patent, the reference patents, and the patent in which the restriction requirement was imposed do not claim any of the same inventions identified by the examiner. The application leading to the ’571 patent was drawn to the same invention that was elected and prosecuted in the parent, restricted application. Therefore, consonance was lacking, the court concluded.

The court also determined that MLC failed to establish that the "as a result of" requirement was met. The ’571/’851/’814 patents ultimately descended from a child application of the restricted application; the child application was originally filed as a continuation-in-part application, rather than a divisional application. The Section 121 safe harbor, by its literal terms, applied only to divisional applications and patents issued on such applications, as well as patents issuing from restricted applications.

Obviousness-type double patenting. Micron argued that claim 1 of the ’571 patent was patentably indistinct from claims 3 or 7 of the ’851 and ’814 patents. Micron also contended that claims 9, 12, 30, 42, and 45 of the ’571 patent were patentably indistinct from claim 7 of the ’851 and ’814 patents.

The court first ruled that the ’851 and ’814 patents could be used as obviousness-type double patenting references against the ’571 patent, even though their applications were filed later than the ’571 patent’s application. The ’571 patent, though earlier-filed, would expire roughly three and a half months after the end of the ’851 and ’814 patents’ terms, so if the ’571 patent were patentably indistinct from the ’851 and ’814 patents, allowing the ’571 patent to remain in force for that extra three and a half months would be an impermissible extension of the ’851 and ’814 patents terms.

Micron failed, however, to meet its burden on summary judgment to show by clear and convincing evidence that the asserted claims of the ’571 patent were invalid due to obviousness-type double patenting, the court decided. There was conflicting evidence on the issue. The parties submitted dueling expert reports that detailed, at length, the experts’ conflicting opinions about the inventions claimed in the ‘571 and ‘851/’814 patents and whether the asserted claims of the ‘571 patent were distinct from and obvious in view of the ‘851/’814 patents. Therefore, summary judgment was not appropriate.

The case is No. 3:14-cv-03657-SI.

Attorneys: Fabio Elia Marino (McDermott Will & Emery) for MLC Intellectual Property, LLC. Michael Richard Headley (Fish & Richardson PC) for Micron Technology, Inc.

Companies: MLC Intellectual Property, LLC; Micron Technology, Inc.

MainStory: TopStory Patent CaliforniaNews

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