Key Highlights
- Sanofi has filed two separate lawsuits in New Jersey federal court against Pfizer and Moderna, alleging both companies’ COVID-19 vaccines infringe mRNA and lipid nanoparticle patents developed by Translate Bio, the Massachusetts biotech Sanofi acquired for $3.2 billion in 2021.
- Sanofi says it is seeking fair compensation for use of its patented technology rather than a halt to vaccine sales, a distinction that helped Pfizer, Moderna, and other exposed companies including Sanofi itself trade higher following the filings.
- The cases join an already crowded field of mRNA patent litigation, including GSK, Bayer, and Alnylam Pharmaceuticals’ prior claims against Pfizer and Moderna, Moderna’s ongoing 2022 infringement suit against Pfizer, and BioNTech’s more recent countersuit against Moderna’s next-generation shot, mNEXSPIKE.
Two Companies, One Shared Technology Dispute
Sanofi’s complaints, filed as Translate Bio Inc v. Pfizer Inc and Translate Bio Inc v. Moderna Inc, target the lipid nanoparticle technology both companies use to deliver mRNA into the body, technology Sanofi says was developed by Translate Bio before its 2021 acquisition. By pursuing both major COVID vaccine makers simultaneously rather than a single target, Sanofi is positioning its claim across essentially the entire mRNA vaccine market built on this delivery approach.
A Compensation Claim, Not a Sales Injunction
Sanofi has been explicit that its goal is fair compensation for use of its patented technology, not an effort to block vaccine sales, a framing that appears to be shaping how the market is pricing the risk. Neither Pfizer nor Moderna had immediately responded to requests for comment following the filings, leaving the companies’ formal legal position still to be established.
Part of a Broader, Long-Running Patent Battle Over mRNA
These new cases extend a multi-year pattern of patent litigation surrounding COVID-19 vaccine technology, joining prior lawsuits from GlaxoSmithKline, Bayer, and Alnylam Pharmaceuticals seeking a share of Pfizer and Moderna’s combined tens of billions of dollars in vaccine revenue. The field is further complicated by Moderna’s own 2022 infringement suit against Pfizer, still ongoing, and BioNTech’s February countersuit alleging Moderna’s newer shot, mNEXSPIKE, infringes one of its patents, underscoring how intertwined and adversarial the IP landscape around mRNA vaccine technology has become.
Sizing the Stakes Against a Shrinking Franchise
With Pfizer’s Comirnaty alone having generated close to $96 billion in revenue from 2021 through the first quarter of 2026, and Moderna having earned roughly $48 billion over a similar stretch, the combined revenue base at stake across both new Sanofi suits is substantial even as current quarterly sales for both companies have fallen sharply. Moderna’s own March settlement of a related lipid-nanoparticle dispute, capped at $2.25 billion, remains one of the few available benchmarks for how litigation of this kind might ultimately be resolved, though differing patents, claims, and legal defenses mean it functions as a scale reference rather than a predictor of outcomes in Sanofi’s new cases.
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