by Dennis Crouch
American Axle & Manufacturing, Inc. v. Neapco Holdings LLC (Fed. Cir. 2019)
This case focuses on Neapco’s U.S. Patent 7,774,911 that D.Del. Judge Stark found to lack eligibility. On appeal a divided panel has affirmed — with Judges Dyk and Taranto supporting invalidity and Judge Moore writing in dissent.
The ‘911 patent covers a method of manufacturing a drive-shaft assembly with an internal-liner that is designed to reduce vibration problems. Yes – the method of manufacture is not patent eligible because it is directed to a law of nature.
One way to see this case is as a battle between Parker v. Flook and Diamond v. Diehr. The majority follows Flook and finds the patent is invalid. As suggested below, the issue here also looks like Halliburton — where the patent “conveniently” uses functional language at the point of novelty. The majority also suggests – but does not decide – that the claims lack enablement and written description.
Essentially, the claim are directed to functional improvement in drive-shaft technology — a drive shaft with an internal liner that has 2-way damping. However, the claims do not require a particular approach to achieving the damping result. Further, according to the majority, the specification does not provide enough guidance to let readers know that something real (beyond a law of nature or abstract idea) is being claimed.
Claim 1 at issue:
A method for manufacturing a shaft assembly of a driveline system … adapted to transmit torque …, the method comprising:
providing a hollow shaft member;
tuning at least one liner to attenuate at least two types of vibration transmitted through the shaft member; and
positioning the at least one liner within the shaft member such that the at least one liner is configured to damp shell-mode-vibrations in the shaft member by an amount that is greater than or equal to about 2%, and the at least one liner is also configured to damp bending-mode-vibrations in the shaft member,
the at least one liner being tuned to within about ±20% of a bending mode natural frequency of the shaft assembly as installed in the driveline system.
Drive shaft technology has been around for a long time and the subject of many patents. One of the earlier U.S. patents is this 1861 Mower Machine (U.S. Patent No. 32,908). Throughout this time, a common problem has been vibration control and various solutions have been the subject of hundreds of patents.
In this case, the core innovation disclosed in the ‘911 patent is that the shaft-liner has been attuned to dampen two types of vibration (shell mode and bending mode) and the patent provides several example shaft liner designs to accomplish this goal:
Critical Over Claiming: Rather than claiming these particular liner shapes, the patent claims a liner that is “attuned” so as to have a particular dampening profile. This is the patentee’s critical error. In addition, the patent does not claim a particular method for attunement — just the functional result. In considering what’s being done here, the Federal Circuit found that the claim is broadly directed to the broad physics principles associated with vibrational frequency and dampening of vibrations:
[The claims] simply state that the liner should be tuned to dampen certain vibrations. Thus, the problem is that the claims’ instruction to tune a liner essentially amounts to the sort of directive prohibited by the Supreme Court in Mayo—i.e. “simply stat[ing] a law of nature while adding the words ‘apply it.’” . . . [T]he mechanisms for achieving the desired result—are not actually claimed.
Since drive shafts and internal liners were already known in the art, the majority found nothing-new there — no inventive step sufficient to transform the abstract idea into a patent eligible invention.
Judge Moore’s dissent is a good read and I’ll save a post on it for this weekend.