A patent specification need enable full scope of the claimed invention
| August 10, 2018
Trustees of Boston University. v. Everlight Electronics Co. Ltd., et al.
July 25, 2018
Before Prost, Moore, and Reyna. Opinion by Prost.
Summary
The Federal Circuit reversed the district court’s denial of Defendants’ motion for JMOL that claim 19 of the asserted patent is invalid for failing to meet the enablement requirement of 35 U.S.C. § 112 because the specification fails to enable full scope of the claimed invention.
Details
Plaintiff Trustees of Boston University (hereinafter “BU”) sued defendants Everlight Electronics Co., Ltd. Et Al. (hereinafter “Everlight”) for infringing U.S. Patent No. 5,686,738 (hereinafter “the ’738 patent”). The district court concluded that Everlight infringed the ’738 patent and the ‘738 patent is valid. Everlight then renewed their motion for judgment as a matter of law (“JMOL”) that the ’738 patent is invalid for non-enablement. The district court denied Everlight’s motion. Everlight appealed that denial, and BU cross-appealed on other issues.
The ‘738 patent is related to light-emitting diodes (“LEDs”), which are semiconductor devices that emit light when an electric current is applied. LEDs typically consist of multiple layers of solid-state materials, which generally have one of three types of crystal lattice structures: (1) monocrystalline, (2) polycrystalline, and (3) a mixture of polycrystalline and amorphous regions. Solid-state materials can also just be amorphous.
Claim 19 of the ‘738 patent is shown as below:
19. A semiconductor device comprising:a substrate, said substrate consisting of a materi- al selected from the group consisting of (100) silicon, (111) silicon, (0001) sapphire, (11–20) sapphire, (1–102) sapphire, (111) gallium are- senide, (100) gallium aresenide, magnesium ox- ide, 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 ni- tride; and
a growth layer grown on the buffer layer, the growth layer comprising gallium nitride and a first dopant material.
In district court, the term “grown on” is construed to mean “formed indirectly or directly above.” Furthermore, to BU’s benefit, the term “a non-single crystalline buffer layer” is broadly construed 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. Thus, assuming a monocrystalline layer as the growth layer, there are six permutations for the relationship between the growth layer and the buffer layer within the scope of claim 19: a monocrystalline growth layer formed directly or indirectly on a polycrystalline buffer layer; a monocrystalline growth layer formed directly or indirectly on a mixture of polycrystalline and amorphous buffer layer, and a monocrystalline growth layer formed directly or indirectly on an amorphous buffer layer.
Everlight contended that claim 19 is not enabled because the ’738 patent’s specification does not teach one of skill in the art how to make one of the six permutations, that is, the claimed semiconductor device with a monocrystalline growth layer grown directly on an amorphous buffer layer. In fact, both parties’ experts testified that it is impossible to epitaxially grow a monocrystalline film directly on an amorphous structure.
In response, BU argued that the ’738 patent does not teach only epitaxy. Furthermore, BU relied on the testimonies from its experts and the inventors arguing that others have successfully grown a monocrystalline layer directly on an amorphous buffer layer, although those were indisputably done after the ’738 patent issued.
First, the Federal Circuit considered that it is difficult to credit BU’s contention that the ‘738 patent does not teach only epitaxy. The specification of the ‘738 patent is merely composed of short four-columns of text, which is saturated with the word “epitaxy” or variants thereof. The specification uses a lot of definite or absolute language indicating that the invention is about the epitaxy. For example, the Abstract of the ‘738 patent recites “[t]his invention relates to a method of preparing highly insulating GaN single crystal films in a molecular beam epitaxial growth chamber.” The present author also note that the specification also lacks any so-called boiler plate language a patent drafter usually used to describe that what disclosed is merely one or more embodiments or examples of the invention.
Furthermore, the Federal Circuit pointed out that the inquiry of enablement is whether the patent’s specification taught one of skill in the art how to make such a device without undue experimentation as of the patent’s effective filing date. Enablement is determined as of the patent’s effective filing date. BU does not suggest these others who have successfully grown a monocrystalline layer directly on an amorphous buffer layer accomplished those by following the present specification’s teachings, nor that achieving these results was within an ordinary artisan’s skill as of the patent’s effective filing date.
Lastly, BU argued, and the district court agreed, that it is sufficient that the ’738 patent enables five out of the six referenced permutations and there is no need to enable the sixth permutation, that is, the claimed device with a monocrystalline growth layer directly on an amorphous buffer layer. The Federal Circuit disagreed, and held that the specification must enable the full scope of the claimed invention. “[T]o 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.’” “[T]he artisan’s knowledge of the prior art and routine experimentation can often fill gaps, interpolate between embodiments, and perhaps even extrapolate beyond the disclosed embodiments, depending upon the predictability of the art.” But this gap-filling is merely supplemental; it cannot substitute for a basic enabling disclosure.
Therefore, the Federal Circuit held that claim 19 is not enabled as a matter of law and accordingly reversed the district court’s denial of Defendants’ motion for JMOL on this issue.
In the end, the Federal Circuit pointed out that BU created its own enablement problem because BU successfully sought a construction of “a non-single crystalline buffer layer” that included a purely amorphous layer in the district court. The Federal Circuit commented that 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.”
Take away
- Patent drafters should avoid using absolute languages in a specification, especially in the Abstract of the specification, which may inadvertently limit the scope of the invention. It is advisable that the patent drafter always describes the invention as one or more embodiments or examples of the present invention.
- Patent drafters should be cautious in pursuing an unreasonable large scope for the independent claim, which may run risk of being invalid due to non-enablement.
