The Fédération Internationale de l'Automobile (FIA) has officially announced that Mercedes has been permitted to introduce upgrades to its power unit, despite vocal opposition from rival teams, most notably Red Bull Racing. This decision forms part of the Additional Development and Upgrade Opportunities (ADUO) framework that the sport’s governing body introduced alongside the rollout of brand‑new engines for the 2026 Formula One season. The ADUO system was designed to give manufacturers a structured pathway to close any performance gaps that emerge during the life of the current technical regulations, ensuring that no team is permanently disadvantaged by an early‑season engine deficit.
In June, after the first five Grand Prix events of the year, the FIA completed its initial performance assessment. The evaluation concluded that Red Bull’s power unit was the benchmark for the season, while Mercedes, Ferrari, Audi and Honda were identified as falling short of the top‑tier performance window. Consequently, the FIA granted those four manufacturers the right to introduce additional homologations – essentially approved upgrades – for the 2026 and 2027 seasons.
Although the FIA did not release a detailed press briefing at the time, the outcome was corroborated by statements from team principals and drivers, and a leaked internal document later confirmed the specifics. The ruling sparked controversy across the paddock. Mercedes, whose works team had dominated the opening six races and secured a string of victories, was now allowed to receive a performance boost, whereas Red Bull, which had managed only a single podium finish in the same period, appeared to be penalised by the decision. The perception that the sport’s regulator was favouring a team that was already ahead of the competition fueled heated debate among fans and commentators alike.
Red Bull’s lead driver, Max Verstappen, publicly criticised the FIA’s findings, arguing that the assessment undermined the competitive balance of the championship. Meanwhile, Mercedes team principal Toto Wolff questioned the transparency of the process, reminding the media in July that his squad possessed "the most powerful power unit" on the grid.
The FIA, for its part, refrained from confirming the details while a second review was underway. The second assessment period concluded at the Hungarian Grand Prix, just before the summer hiatus. The FIA released a comprehensive statement that confirmed the earlier June decisions and added new information about the subsequent review.
For the first period, the statement read: "Mercedes were determined to be within the two‑to‑four per cent performance window and will therefore be allowed one additional homologation in 2026 and another in 2027, together with corresponding increases to the cost cap and dyno testing allowances. Audi, Ferrari and Honda were found to be more than four per cent behind the lead and will each receive two additional homologations in both 2026 and 2027, also with adjusted cost‑cap and testing provisions." The second‑period findings were less generous for Red Bull. The FIA announced that no further homologations would be granted to any power‑unit manufacturer for the next review window.
This effectively means that Red Bull’s engine is now considered to be operating within two per cent of the best unit on the grid – a margin that could be interpreted as the benchmark itself. Had any of the other manufacturers demonstrated a performance jump sufficient to overtake Red Bull after June, the British team would have been eligible for its own upgrade, but the data did not support that scenario. In the drivers' championship, Mercedes’ Kimi Antonelli (a fictional placeholder for the purpose of this rewrite) leads his teammate George Russell and Ferrari’s Lewis Hamilton by 59 points, while Verstappen trails by a substantial 130 points, sitting in sixth place. The constructors' standings show Mercedes ahead of Ferrari by 87 points, with McLaren – who also run Mercedes power units – climbing to third after Lando Norris secured back‑to‑back victories in the most recent races.
Despite having the green light to implement their 2026 upgrade since the June announcement, Mercedes have not yet deployed the new hardware on track. Ferrari, Audi and Honda are believed to have each introduced one of their two allotted upgrades for the season, but the full suite of improvements remains to be seen.
FIA single‑seater director Nikolas Tombazis defended the robustness of the ADUO review process, stating: "The FIA has undertaken thorough and exhaustive analysis as part of our ADUO review process. With the release of the findings of period two, we are confident that, based on the quality of the data, its analysis is incredibly robust, giving us a high level of confidence in our findings.
We also have to respect the confidentiality and intellectual property of the teams and their Power Unit Manufacturers in disseminating any details from the findings. This is the first year of ADUO so naturally there are areas which we may evolve over time, in discussion with all the PU Manufacturers." The third ADUO review window opened at the Dutch Grand Prix and will run through to the Mexico City Grand Prix on 1 November, giving manufacturers another opportunity to submit performance data and potentially earn further upgrades before the season concludes. As the championship heads toward its final races, the strategic deployment of these upgrades could prove decisive in the battle for both drivers' and constructors' titles.
Looking ahead, Formula 1 will travel to Monza for Ferrari’s home Grand Prix on 4‑6 September, a race that traditionally offers a high‑speed test of engine performance. Fans can follow the action live on Sky Sports F1 or stream the coverage via NOW without a long‑term contract, and can stay updated with the latest analysis on The F1 Show podcast and Sky Sports’ WhatsApp channel. The evolving ADUO landscape adds another layer of intrigue to an already dramatic season, as teams balance the pursuit of speed with the regulatory constraints that shape the sport’s technological future.