The allegation is not that Sanofi competed hard. It is that the company may have crossed the legal line between comparative argument and misleading conduct capable of excluding a rival. The Commission said it will examine whether Sanofi implemented a campaign targeting healthcare professionals and healthcare payers with allegedly misleading information about Fluad, a rival product made by CSL Seqirus.
The products at issue are Sanofi's Efluelda and CSL Seqirus's Fluad. The Commission described both as high-dose or enhanced flu vaccines used for older adults, a market where clinical evidence, payer confidence and professional guidance can shape demand before an individual patient ever sees a prescription.
That is why the case belongs in competition law rather than ordinary product promotion. Article 102 of the Treaty on the Functioning of the European Union prohibits abuse of a dominant position where it may affect trade between member states. In plain terms, a dominant company can make strong claims about its own product, but EU law gives regulators room to intervene if conduct distorts competition by misleading customers or blocking rivals rather than by winning on the merits.
The health setting raises the stakes without lowering the legal standard. Older adults are a priority group for flu vaccination, and public buyers often depend on expert advice when deciding which products to fund or recommend. If the information channel is distorted, the commercial effect can run through procurement systems rather than individual consumer choice.
The Commission has not found that Sanofi broke the law. Its announcement says the opening of a formal investigation does not prejudge the outcome, and that there is no legal deadline for completing antitrust investigations. That procedural caution is central: the case is an inquiry into suspected conduct, not a ruling on liability.