Synopsys brought a patent infringement action against Mentor Graphics in the Northern District of California, alleging infringement of various claims of U.S. Patent Nos. 5,530,841, 5,680,318, 5,748,488, and 6,836,420. Claim 1 of the '841 patent recites:
A method for converting a hardware independent user description of a logic circuit, that includes flow control statements including an IF statement and a GOTO statement, and directive statements that define levels of logic signals, into logic circuit hardware components comprising:
converting the flow control statements and directive statements in the user description for a logic signal Q into an assignment condition AL(Q) for an asynchronous load function AL( ) and an assignment condition AD(Q) for an asynchronous data function AD( ); and
generating a level sensitive latch when both said assignment condition AL(Q) and said assignment condition AD(Q) are nonconstant;
wherein said assignment condition AD(Q) is a signal on a data input line of said flow through latch;
said assignment condition AL(Q) is a signal on a latch gate line of said flow through latch; and
an output signal of said flow through latch is said logic signal Q.
In short, the invention provides for conversion of a user's functional description of a logic circuit into an arrangement of hardware components that perform the logic circuit's functions.
Traditionally, a user would specify the hardware components for fabrication. But, as circuit complexity grew, this task because complex and cumbersome. Hardware description languages (HDLs) were created that allow the user to specify the desired operation of the logic circuit, rather than its components and interconnects. Early HDLs still required that the user specify some aspects of the components and interconnects. The '841 patent, as well as the other patents-in-suit, describe a way to translate functional descriptions in an HDL to hardware component descriptions without requiring that the user specify any hardware components. Notably, the claims recite translating one type of logical description to another -- no actual components are required to be arranged or built.
The District Court construed the claims as not requiring the use of a computer, or any other type of hardware. This construction was not challenged by the parties.
Mentor Graphics moved for summary judgment, contending that the claims were ineligible under 35 U.S.C. § 101. The District Court granted this motion, stating that "each of the steps in the claimed methods can be performed by a skilled designer either mentally or with pencil and paper," and that the claims were broad enough to cover an abstract mental process. Further, the District Court noted that the process had previously been performed mentally by the inventors. Finding that the claimed process therefore preempted a "building block of human ingenuity," the District Court found the asserted claims of the '841, '318, and '488 patents to be ineligible (the claims of the '420 patent had previously been ruled to be obvious in an inter partes review).
On review, the Federal Circuit applied the two-prong patent-eligibility test as set forth by the Supreme Court in Alice Corp. v. CLS Bank Int'l. According to the test, one must first determine whether the claim at hand is directed to a judicially-excluded law of nature, a natural phenomenon, or an abstract idea. If so, then one must further determine whether any element, or combination of elements, in the claim is sufficient to ensure that the claim amounts to significantly more than the judicial exclusion. But generic computer implementation of an otherwise abstract process does not qualify as "significantly more." A goal of this test is to prevent one from patenting judicial exclusions, and thereby preempting others from using these basic scientific tools.
Applying the first prong, the Court cited its CyberSource Corp. v. Retail Decisions, Inc. case for the principle that mental processes are ineligible abstract ideas, as such processes (in the Court's view) are basic scientific tools. With reference to claim 1, the Court noted that the method as claimed could be performed mentally or with pencil and paper. This conclusion was supported by admissions as much by the inventors, as well as the District Court's claim construction.
Synopsis argued that, in practice, the claimed invention would have to be performed on a computer to carry out any meaningful conversion. But the Court shut down this line of reasoning, because the claims "are so broad as to read on an individual performing the claimed steps mentally or with pencil and paper." Further, the Federal Circuit's recent reasoning in the Enfish, LLC v. Microsoft Corp. and McRO, Inc. v. Bandai Namco Games Am. Inc. cases did not apply. These cases held that an improvement to computer technology or a computer itself can be enough to lift an invention over the eligibly threshold. Since a computer need not be involved in the carrying out of the claimed invention, the claims cannot be viewed as such an improvement.
Regarding preemption, Synopsis argued that the claims did not preempt all ways of converting functional descriptions of logic circuits to hardware component descriptions thereof. However, the Court quickly (and in a circular fashion) dismissed this notion, stating that "[w]here a patent's claims are deemed only to disclose patent-ineligible subject matter under the [Alice] framework, as they are in this case, preemption concerns are fully addressed and made moot."
Applying the second prong, the Court looked for an inventive concept in the claims. Synopsys's arguments relied on a well-worn notion -- that an inventive concept can be established by the absence of anticipation or obviousness. This line of reasoning, however, has been frequently and consistently rejected by the Court.
Here, the Court noted that an inventive concept can include technical solutions, such as those present in the claims of DDR Holdings v. Hotels.com and BASCOM Global Internet Servs. v. AT&T Mobility. Particularly, the Court observed that the only claim elements that went beyond the abstract idea of "translating a functional description of a logic circuit into a hardware component description of the logic circuit" were the use of assignment conditions. But these elements served to "merely aid in mental translation as opposed to computer efficacy," and were therefore insufficient to provide a technical advance.
Consequently, the claims failed to satisfy the second prong of Alice, and were rendered ineligible as a result.
This case provides yet another illustration of how a technical tool, when not claimed properly, can be deemed non-technical by a reviewing court. Granted, the claims here were drafted well before the Alice decision and satisfied the USPTO's requirements at that time, so we should not criticize their author too harshly.
An argument that might have been more viable than those presented in this case was that the claims were not directed to a fundamental building block or scientific tool -- instead they recited an arrangement of a number of such tools (e.g., HDL specifications, control flow logic, and the mapping thereof into digital logic). Still, such a point may have been dead on arrival due to the patentee's admissions that the claimed invention could be and had been performed manually.
Which brings us to that very issue. In McRO, the Federal Circuit appeared to take the position that there is a difference between merely automating a known manual process and automating a process that is not known to have been previously performed manually. Namely, the former is not patent-eligible while the opposite can be true for the latter. This case does not contradict McRO's holding, as the Court repeatedly emphasized evidence that the inventors had been performing the claimed process manually. Nonetheless, this is an area that the Federal Circuit should clarify, as a distinction between the eligibility of processes that have been performed manually and processes that theoretically could be performed manually may provide ways of protecting complex software inventions that, in practice, require computer implementation to provide results of any significance.
Synopsis, Inc. v. Mentor Graphics Corp. (Fed. Cir. 2016)
Panel: Circuit Judges Lourie, Moore, and Chen
Opinion by Circuit Judge Chen
