What Is a Patent Troll? (And Why They're So Controversial)

"Patent troll" is an insult masquerading as a legal term. The more neutral phrase is non-practicing entity (NPE) — a company that holds patents but doesn't manufacture the products or deliver the services those patents cover. Instead, it generates revenue by licensing those patents, typically under threat of litigation.

Whether that's predatory or legitimate depends enormously on who you ask.

Where the term came from

The phrase "patent troll" was coined around 2001 by Peter Detkin, then an Intel attorney, to describe companies that were shaking down technology firms with dubious patent claims. Intel itself had been sued hundreds of times. Detkin wanted a term that captured what he saw as the parasitic nature of the practice.

The earlier, politer term was "patent assertion entity" (PAE). Academics and economists often use NPE. The industry uses "patent troll." The entities themselves prefer "patent licensing company" or "patent monetization firm."

What NPEs actually do

The model is simple: acquire patents (from failed startups, bankrupt companies, inventors who can't afford to enforce their own IP, or universities), then send demand letters to companies that might be infringing. Most recipients settle rather than litigate — litigation is expensive, and even a groundless patent suit can cost $3–5 million to defend through trial.

NPEs rarely want to go to trial. They want nuisance-value settlements: amounts large enough to justify the demand but small enough that recipients choose settlement over fight. A $150,000 settlement offer against a $3 million litigation defense cost is not a hard calculation.

The landmark cases

NTP v. Research In Motion (BlackBerry) — The defining early patent troll case. NTP held patents on wireless email technology. RIM's BlackBerry allegedly infringed. NTP had no products. The case dragged on from 2001 to 2006, culminating in a $612.5 million settlement — paid one day before the court was to consider an injunction that would have shut down BlackBerry service in the United States for millions of users. The settlement amount shocked the industry.

Lodsys v. App Developers — In 2011, Lodsys, an NPE backed by Intellectual Ventures, sued small independent app developers for using in-app purchase functionality in iOS apps. The developers were paying Apple for the right to use those APIs; Lodsys claimed they needed a separate license directly from Lodsys. Apple and Google eventually intervened to defend their developer ecosystems, but the damage was done — the message was that even tiny developers were targets.

Why patent trolls are legal

They're legal because the patent system is designed around property rights, not manufacturing obligations. A patent is a right to exclude — to prevent others from making, using, selling, or importing the patented invention. Nothing in the statute requires the patent holder to practice the invention. A university can hold a biotech patent and license it without ever running a lab. An individual inventor can patent a process and license it without ever operating a factory.

The same property right that lets Pfizer protect a drug compound lets a shell company hold a software patent and send demand letters to every e-commerce site on the internet.

Alice Corp v. CLS Bank: the Supreme Court changes the game

In 2014, the Supreme Court's decision in Alice Corp. v. CLS Bank International dramatically changed the landscape for software patents. The Court held that implementing an abstract idea on a computer — without more — is not patentable. The claims at issue covered a computer-implemented scheme for mitigating settlement risk in financial transactions. The Court found them patent-ineligible.

The Alice decision invalidated thousands of software patents that had been the primary weapons in the NPE arsenal. Courts began striking down patents that claimed "do [abstract process] on a computer" with dramatically increased frequency. The number of software patent suits from NPEs dropped significantly in the years following Alice.

But Alice didn't kill software patents — it raised the bar. Patents that claim specific technical solutions to specific technical problems, rather than abstract methods implemented generically on computers, remain valid. The NPE model adapted.

How to defend against a patent troll

1. Inter Partes Review (IPR) — The most powerful defense. IPR is a USPTO proceeding that allows anyone to challenge a granted patent's validity based on prior art. It's faster than district court litigation (12–18 months vs. 3–5 years), cheaper, and conducted before technically expert patent judges. The patent invalidation rate in IPR is high — historically around 60–80% of challenged claims don't survive. NPEs hate IPRs because they threaten the entire patent, not just the accused products.

2. Prior art challenges — Even before filing IPR, aggressive prior art searching can reveal that the claimed invention was already known before the patent's priority date. Good prior art changes the settlement calculus dramatically.

3. The "efficient infringer" strategy — Large companies sometimes deliberately infringe, calculating that licensing costs exceed litigation risk. This is controversial and carries real legal risk, but it's a documented practice. Some companies bank on the NPE not wanting to litigate.

4. Alice motions — If the patent covers abstract software functionality, a motion to dismiss under Alice can dispose of the case early and cheaply.

5. Fee-shifting under Octane Fitness — Since the Supreme Court's 2014 Octane Fitness decision, courts can more easily award attorney fees to prevailing defendants in "exceptional" patent cases. A credible threat of fee-shifting discourages frivolous NPE suits.

The legitimate side of the NPE model

Not everyone using the NPE model is a troll. Universities license patents they hold on faculty research — the Bayh-Dole Act of 1980 was specifically designed to enable this. The Broad Institute holds CRISPR patents and licenses them to biotech companies. Individual inventors with legitimate inventions and no resources to manufacture benefit from firms that will enforce their patents for them.

The controversy is about bad-faith assertion of low-quality patents — not about licensing as a business model. The distinction matters, though in practice it can be difficult to draw in real time.

You can explore specific patent records — including patents commonly cited in troll litigation — in the PatentBrief patent browser.

PatentBrief is not a law firm. Nothing here is legal advice. Consult a qualified IP attorney if you receive a patent demand letter.