Precision or Perish:
The Federal Circuit’s New Reality for Patentees

September 8, 2025

Patent law has always wrestled with the tension between protecting innovation and ensuring public clarity. Two recent Federal Circuit decisions—Alnylam v. Moderna and LabCorp v. Qiagen—offer a sharp reminder that the pendulum is swinging toward predictability and precision, even at the cost of flexibility for patentees. Both cases involved sophisticated biotechnology patents, yet their lessons reach across industries: in today’s climate, ambiguity is a liability.

When Definitions Become Iron Shackles

In Alnylam v. Moderna, the Federal Circuit enforced a basic but often overlooked principle: when a patentee defines a term, that definition governs. Alnylam had expressly defined “branched alkyl” in its patent as requiring a carbon atom bound to three others. Years later, when asserting infringement against Moderna’s COVID-19 vaccine technology, it argued for a broader interpretation. The court rejected that effort. Alnylam’s own definitional choice, once made, became an iron shackle.

This holding is not new—it echoes Phillips v. AWH, the touchstone case on claim construction—but it is a powerful reminder of how unforgiving courts can be when lexicography collides with litigation strategy. In an era where patents underpin billion-dollar markets, words chosen in drafting rooms a decade ago can dictate outcomes in the most high-stakes disputes.

When Juries Overreach and Equivalents Fall Short

LabCorp v. Qiagen tells the same story of judicial insistence on clarity, but from a different angle. The case turned on the word “identical.” The district court permitted the jury to treat “identical” as “identical to a portion,” effectively broadening the claim through deliberation. The Federal Circuit reversed, reminding us that claim construction is a matter of law, not jury discretion.

The decision also reinforced the narrow pathway of the doctrine of equivalents. LabCorp’s experts gestured toward similarity but failed to supply the granular, element-by-element proof required under the function–way–result test. The verdict unraveled. Just as in Alnylam, the lesson was uncompromising: precision is non-negotiable, and ambiguity will not be rewarded.

A Judicial Philosophy Emerges

Viewed together, Alnylam and LabCorp embody more than just case-specific holdings. They reflect a judicial philosophy that favors predictability and notice over elasticity. The Federal Circuit is signaling skepticism toward arguments that stretch claim scope—whether through post hoc definitional shifts or through loose appeals to equivalency.

This is not an accident. In recent years, courts have grown wary of jury variability in complex patent cases, particularly in the life sciences where technical nuance abounds. By tightening control over claim construction and demanding rigor in evidence, the Federal Circuit is reinforcing a policy balance: patents must clearly mark their boundaries to preserve public reliance and to ensure innovation incentives are aligned with the disclosure bargain.

Beyond Biotech: Ripple Effects Across Industries

While these cases arise from biotechnology, the message carries far beyond. In artificial intelligence, for instance, disputes are already emerging over how to construe technical terms such as “training data” or “token embedding.” In pharmaceuticals, equivalents may be invoked to capture biosimilars that are functionally close but structurally distinct. In materials science, subtle definitional choices can decide whether a new alloy or polymer falls within the scope of a claim.

The broader point is this: whether in chemistry, software, or AI, courts are applying the same exacting standards. Ambiguity in drafting, casual reliance on jury sympathy, or vague evidentiary showings are no longer viable strategies. Companies that treat patents as flexible tools will find themselves constrained by the very precision they neglected to enforce.

Strategic Takeaways for Innovators

For clients, the implications are clear. First, the front end of patenting—the drafting stage—demands extraordinary care. Definitions should not be inserted lightly, because once provided, they will control. Second, litigation strategies must be built on rigorous, detail-rich evidence. Courts will not rescue patentees with expansive interpretations or broad appeals to fairness.

Third, portfolio management must be proactive. Companies should revisit existing patents with an eye toward whether definitional choices could later limit enforcement. They should also plan R&D disclosures and claim strategies with long-term business goals in mind, anticipating how courts may interpret their words years down the line.

Finally, businesses must recognize that the Federal Circuit’s tightening approach may alter settlement dynamics, licensing negotiations, and even investment decisions. A portfolio seen as ambiguous may lose value; one built on clarity may command a premium.

Positioning for the Future

Alnylam and LabCorp are not just about lipid chemistry or DNA sequencing. They are bellwethers of a broader shift in patent law: a move toward clarity, predictability, and judicial control. This shift serves a policy function—ensuring the patent system delivers reliable notice and does not chill follow-on innovation. But for patentees, it means the margin for error is shrinking.

At Daly Law & Strategy, we see these cases as part of a larger trend reshaping intellectual property strategy. Our role is to help clients anticipate where the doctrine is heading, not just react to where it has been. With expertise at the intersection of law, science, and business, we guide innovators in drafting stronger patents, structuring more defensible portfolios, and litigating with the rigor the Federal Circuit now demands.

The lesson from these cases is clear: in today’s patent system, precision is power. Those who master it will shape the future of innovation.