Magsil Corporation v. Hitachi Storage Technologies (Fed. Cir., 2012) 

Thus we descended into the fourth chasm,
Gaining still farther on the dolesome shore
Which all the woe of the universe insacks.  
–The Inferno, Canto VII, Dante Alighieri

Although patent validity is more frequently challenged on the basis of uncited or ill-considered prior art, Section 112 issues, including the requirement of an enabling disclosure, are underutilized as a basis of attack.  The recent decision in Magsil Corporation v. Hitachi Storage Technologies (Fed. Cir., decided August 14, 2012) may help to reverse that.

The Delaware District Court granted summary judgment of invalidity of certain claims of U.S. Pat. No. 5,629,922 for lack of enablement, and the Federal Circuit affirmed.  The ‘922 patent was assigned to the Massachusetts Institute of Technology and subsequently licensed exclusively to MagSil Corporation.

The invention related to read-write sensors for hard drive storage systems.  In particular, the claims defined trilayer tunnel junctions comprising two ferromagnetic electrodes and an electrical insulator.  Electric current can “tunnel” (quantum mechanically) through the insulator and pass from one electrode to the other.  The resistance is high when the magnetization directions are antiparallel and low when they are parallel.  Thus, a change in magnetization direction in one electrode can effect a resistance change in the device.  In the claimed device, “applying a small magnitude of electromagnetic energy to the junction reverses at least one of the magnetization directions and causes a change in the resistance by at least 10% at room temperature.”

The concept had long been known.  However, the inventors were the first to demonstrate (in 1995) that up to an 11.8% change could be achieved by improving the electrode surfaces and insulator quality.  By the time MagSil sued Hitachi in December 2008, improvements in such tunnel junctions had allowed a more than 600% change in resistance.

An invalidity challenge based on non-enablement requires clear and convincing evidence.  To be enabling, the specification of a patent “must teach those skilled in the art how to make and use the full scope of the claimed invention without undue experimentation.”  Genentech, Inc. v. Novo Nordisk, A/S, 108 F.2d 1557, 1561 (Fed. Cir. 1997).

As Judge Rader wrote, “[t]his important doctrine prevents both inadequate disclosure of an invention and overbroad claiming that might otherwise attempt to cover more than was actually invented.  Thus, a patentee chooses broad claim language at the peril of losing any claim that cannot be enabled across its full scope of coverage.”

The district court found that the asserted claims cover “resistance changes . . . up to infinity.”  Nowhere had MagSil “disclaimed” the infinite scope.  Its experts testified that even a 1000% change in resistance would fall within the claims despite their own admissions that such results were unknown in 1995.  The MIT specification cited a 1975 paper that predicted an ideal maximum of only a 24% change in resistance, and 20 years later, only about half that value had been achieved.  One MagSil expert testified that a 100-120% change in resistance was achievable “without undue experimentation,” yet this level wasn’t actually realized until at least 2006.  Moreover, the same expert admitted that even someone with extraordinary skill would not have known in 1995 how to select the materials and processes necessary to achieve the 100-120% change.

The specification “enabled a marginal advance over the prior art, but did not enable at the time of filing a tunnel junction of resistive changes reaching even up to 20%, let alone the more recent achievements above 600%,” according to Federal Circuit.

The unanimous panel found the instant facts analogous to those of In re Fisher, 427 F.2d 833, 839 (CCPA 1970), where the court held a claim with an unbounded upper limit to be non-enabling.  In Fisher, the claims were drawn to a system for producing substances containing adrenocorticotropic hormone (ACTH) that were suitable for injection into humans to stimulate the adrenal gland.  The claims recited a potency of “at least one International Unit of ACTH per milligram,” while the prior art had taught a maximum of 0.5 IUs.  However, the inventors’ compositions maxed out at 2.3 IUs.  In rejecting the open-ended claim, the court declined to allow one inventor “to dominate all such compositions having potencies greater than 1.0, including future compositions having potencies far in excess of those obtainable from [the inventor’s] teachings plus ordinary skill.”

The Federal Circuit showed little compassion for MagSil, calling its difficulties “a problem of its own making.”    The enablement doctrine’s “prevention of over broad claims ensures that the patent system preserves necessary incentives for follow-on improvement inventions.”

Of course, patent examiners are human, applicants and their lawyers can and do claim too ambitiously, and Heisenberg’s uncertainty principle lives.  Consequently, even without the aid of quantum theory, plenty of applications with overly broad claims “tunnel” through the lack-of-enablement barrier to achieve patent-hood.  Then it’s up to us challengers to raise the Section 112 banner with zeal and battle our foe until the ill-framed right-to-exclude plummets to the depths of the inferno.

-Jon Schuchardt
Check out Jon’s bio page

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