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How not to draft a patent claim
Antivirus software left vulnerable to patent eligibility challenge
A software patent holder learned the hard way how critical drafting is to surviving patent-eligibility challenges. The U.S. Court of Appeals for the Federal Circuit found the asserted software claims were directed to an “abstract idea” because the claims failed to require many of the technological improvements described in the patents’ specifications — but the patentee may still come out on top.
Patentee prevails at trial
The Trustees of Columbia University hold two patents for antivirus software. Historically, antivirus programs worked by comparing suspicious code against a database of known viruses, thus allowing new viruses to fly under the radar.
Columbia developed a process in which an “emulator” executes part of a program and compares its performance against a “model of function calls” that reflects how the program is typically expected to perform. The goal is to identify whether the emulated program is behaving anomalously.
According to the patent claims, the model of function calls is “a combined model created from at least two models created using different computers.” Columbia sued Gen Digital, which markets Norton software, for patent infringement. Gen Digital sought a pretrial judgment that the asserted claims were patent-ineligible abstract ideas, but the trial court denied the motion. After a trial, a jury found Gen Digital willfully infringed the patents and awarded damages of $185 million. Gen Digital appealed.
Patent claims run into the Alice firewall
The Federal Circuit rejected the trial court’s finding that the asserted claims were patent-eligible under the two-step Alice framework for patent eligibility. Under the first step of the Alice analysis, courts determine whether claims are “directed to” a patent-ineligible concept, such as an abstract idea. If they are, the court proceeds to the second step and determines whether the claims contain an “inventive concept” sufficient to transform the abstract idea into patent-eligible subject matter.
In software cases, the first step often turns on whether the claims are directed to a specific technological improvement in computer functionality or instead merely use computers as tools to perform an abstract idea. Software-based inventions have been found patent-eligible when they improve the functioning of computer technology itself. But claims that merely invoke conventional computer technology to perform longstanding concepts generally don’t suffice.
The Federal Circuit concluded that the asserted claims were directed to the abstract idea of comparing data against a model to determine whether the data is anomalous. The court emphasized that though the patents’ specifications described various technological improvements, the claim language itself didn’t require many of those features.
Columbia conceded that emulators were conventional technology and that using multiple computers collaboratively in a divide-and-conquer fashion was itself an abstract idea. Columbia nevertheless argued that the claims described several other technological improvements that rendered the inventions patent-eligible. The court disagreed, explaining: “It cannot be said the claims are directed to a technological improvement when nothing in the claims requires the steps necessary to make the improvement.”
The Federal Circuit nevertheless threw Columbia a lifeline at the second step of the Alice analysis. The court concluded that Columbia had preserved an argument that the claimed model of function calls might provide the necessary inventive concept to support patent eligibility. The Federal Circuit therefore returned the case to the trial court to determine whether the claimed model of function calls supplies an inventive concept sufficient to transform the abstract idea into patent-eligible subject matter.
Beyond the abstract
The appellate court also addressed several other issues on appeal that could become relevant on remand. These included the propriety of damages for foreign sales (see “When are foreign sales of software relevant to damages?” on page X), the trial court’s award of enhanced damages and a finding of willful infringement. Based on the Federal Circuit’s rulings, even if the lower court ultimately finds the claims patent-eligible, the damages award will likely be significantly reduced.
Sidebar: When are foreign sales of software relevant to damages?
About $94 million of the jury’s $185 million verdict in the Gen Digital case (see main article) was based on sales to customers outside the United States. Generally, no infringement occurs when a patented product is made and sold in another country. But the jury found that the infringing software sold to foreign customers was made in, and distributed from, the United States. The Federal Circuit disagreed.
The court explained that software in the abstract — that is, software not physically encoded in a tangible copy, such as a CD, hard drive or other computer-readable medium — is more like a blueprint. According to the court, software isn’t tangible or capable of infringement until it’s encoded in a particular copy stored on a computer-readable medium.
Because the software products sold to foreign customers weren’t installed on computers in the United States, the court concluded they were made outside the United States. As a result, if the asserted patent claims are ultimately found patent-eligible on remand, the damages calculation must exclude those foreign sales.
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