By Jason Rantanen
Trustees of Boston University v. Everlight Electronics Co., Ltd. (Fed. Cir. 2018) Download Opinion
Panel: Prost (author), Moore, Reyna
This opinion provides an example of how Section 112 can function as a commensurability requirement. The court’s final lines say as much:
“Having obtained a claim construction that included a purely amorphous
layer within the scope of the claim, BU then needed to successfully defend against an enablement challenge as to the claim’s full scope…Put differently, if BU wanted to exclude others from what it regarded as its invention, its patent needed to teach the public how to make and use that invention. That is ‘part of the quid pro quo of the patent bargain.'”
Slip Op. at 14 (citations omitted).
I like the opinion because the court’s analysis fits neatly with my conceptual explanation of how enablement analyses are actually performed: it’s a two-step process, with the first step being the articulation of the relevant target and the second asking whether the patentee managed to hit that target. Here, the court defined the target as consisting of one of six possible permutations under the claim construction the patent owner had sought. Unfortunately, the evidence did not support the conclusion that a person having ordinary skill in the art could make that permutation without undue experimentation.
In the Federal Circuit’s words, Patent No. 5,686,738 “relates to the preparation of monocrystalline GaN films via molecular beam epitaxy.” Slip Op. at 4. These films are used in creating blue light LEDs. The plaintiff, Trustees of Boston University (BU), sued defendants for infringing the ‘738 patent. Following a jury trial, BU obtained a verdict of infringement and no invalidity. The district judge subsequently denied defendants’ renewed motion for judgment as a matter of law, in which defendants had argued that the asserted claim was not enabled. Defendants appealed.
Only claim 19 of the ‘738 patent was at issue. That claim states:
A semiconductor device comprising:
a substrate, said substrate consisting of a material selected from the group consisting of (100) silicon, (111) silicon, (0001) sapphire, (11-20) sapphire, (1-102) sapphire, (111) gallium aresenide, (100) gallium aresenide, magnesium oxide, zinc oxide and silicon carbide;
a non-single crystalline buffer layer, comprising a first material grown on said substrate, the first material consisting essentially of gallium nitride; and
a growth layer grown on the buffer layer, the growth layer comprising gallium nitride and a first dopant material.
Two constructions were key here. The court construed “grown on” to mean “formed indirectly or directly above” and “a non-single crystalline buffer layer” to mean “a layer of material that is not monocrystalline, namely, [1] polycrystalline, [2] amorphous or [3] a mixture of polycrystalline and amorphous, located between the first substrate and the first growth layer.” (emphasis added). It also understood “growth layer” as including within its scope a monocrystalline growth layer. BU did not challenge any of these constructions on appeal.
In the Federal Circuit’s view, collectively these constructions raised six possible permutations for the relationship between growth layer and buffer layer:
- (1) monocrystalline growth layer formed indirectly on a polycrystalline buffer layer;
- (2) monocrystalline growth layer formed indirectly on a buffer layer that is a mixture of polycrystalline and amorphous;
- (3) monocrystalline growth layer formed indirectly on an amorphous buffer
layer;
- (4) monocrystalline growth layer formed directly on a polycrystalline buffer layer; (5) monocrystalline growth layer formed directly on a buffer layer that is a mixture of polycrystalline and amorphous; and
- (6) monocrystalline growth layer formed directly on an amorphous buffer layer.
Slip Op. at 6. Of these six permutations, defendants focused their enablement argument on #6: whether a person of ordinary skill in the art could practice the invention with a monocrystalline growth layer formed directly on an amorphous buffer layer.
With the court’s attention focused on permutation #6, the enablement analysis was relatively straightforward. The evidence supporting enablement of #6 was weak: the only technique described in the patent, epitaxy, doesn’t work to grow a growth layer directly on an amorphous structure. BU tried to argue that the patent didn’t actually teach epitaxy, but the court was unpersuaded: “The ’738 patent’s specification is concise—just over four columns of text—and focuses on epitaxy. Indeed, it is saturated with the word ‘epitaxy’ or variants thereof.” Id. at 9. BU also argued that what the patent taught could not be epitaxy “because epitaxy invovles a crystalline layer on top of another crystalline layer,” and an amorphous layer is not “crystalline.” Id. at 10. But regardless of whether one called it epitaxy or not, the problem was that BU couldn’t identify anywhere in the specification that taught how to grow a monocrystalline layer directly on an amorphous layer. Nor was the expert testimony sufficient as it consisted of conclusory statements. Testimony that other people had successfully grown a monocrystalline layer on top of an amorphous buffer layer didn’t help either, as “[s]imply observing that it could be done–years after the patent’s effective filing date–bears little on the enablement inquiry.” Id. at 12.
In light of how the court understood the focus of the enablement issue, BU’s final argument–that the specification enabled 5 out of the 6 permutations and that was enough–didn’t work. The court cited the “full scope” language from precedent here, and the “gap-filling” approach didn’t work here since that concept “is merely supplemental; it cannot substitute for a basic enabling disclosure.” Ultimately, the court concluded that the patent needed to enable all six permutations–a result consistent, the court noted, with the claim constructions that BU itself had sought. In the end, the court saw this as being in the vein of Liebel-Flarsheim: if you get the claim scope you ask for through construction, you’re also going to need to show enablement of that scope.
For enablement-timing gurus, there’s some interesting language in the section about the post-application successes to ponder.