F1's ousted fuel flow meter supplier sues replacement over patent infringement ahead of US GP

Sentronics Holdings Ltd, the FIA’s exclusive fuel flow meter supplier until the end of 2025, has filed a patent infringement lawsuit against its successor Allengra GmbH in the US District Court for the Western District of Texas, with the case lodged on 16 October — just days before the United States Grand Prix in Austin.

The British company claims that the sensors Allengra now supplies to every car on the grid infringe its US patent 11,391,609, a “Flow meter” patent granted in July 2022. According to the complaint, as reported by PlanetF1, Sentronics held the FIA contract from 2018 to 2025 before Allengra, a German manufacturer, won the tender for the 2026–2030 cycle in November 2024.

What fuel flow meters do

Fuel flow meters track exactly how much fuel reaches each engine, giving the FIA a mechanism to enforce the flow-rate limits written into the technical regulations. Because fuel flow directly determines the power output of the internal combustion engine, the FIA treats accurate metering as a core policing tool.

Sentronics’ patent covers a specific ultrasonic measurement method: pairs of signals are sent in opposite directions through the fuel, and their phase difference is used to calculate flow rate. The principle exploits the fact that ultrasonic signals travel faster when moving with a fluid than against it.

How the dispute developed

According to the complaint, Sentronics conducted its own laboratory testing in late 2024 and concluded that Allengra’s meters replicate its patented method. The filing also states that Sentronics had previously shared technical details with the FIA under a non-disclosure agreement, and that the FIA confirmed receiving a formal notice from Sentronics on 17 September 2025, responding that its contents were “duly noted”.

Sentronics alleges the infringement was deliberate, noting that Allengra was informed of the European equivalent of the patent in August 2025. Sentronics’ lawyers followed up with a demand letter in April 2026, which Allengra’s US counsel disputed.

Beyond direct infringement, Sentronics accuses Allengra of inducing the FIA and the teams to use the meters on US soil — specifically at races in Austin, Miami and Las Vegas.

What Sentronics wants

Sentronics has demanded a jury trial and filed two exhibits alongside its complaint. The company is asking the court to permanently prohibit Allengra from manufacturing, selling or supplying the meters in the United States, and is also seeking financial damages. Allengra has not yet publicly responded to the lawsuit.