The governing body for Formula One, the FIA, has officially confirmed that Mercedes has been given permission to introduce upgrades to its power unit, despite objections from rival teams, most notably Red Bull. This decision forms part of the Additional Development and Upgrade Opportunities (ADUO) framework that the FIA introduced alongside the rollout of brand‑new engines for the 2026 season.
ADUO was designed to give manufacturers a structured way to close any performance gap that may emerge during the life of the regulations, ensuring that no team is permanently disadvantaged by an early‑season engine shortfall. The first ADUO assessment took place after the opening five races of the 2024 campaign. At that point, the FIA evaluated the relative performance of each power‑unit supplier and concluded that Red Bull’s Honda‑derived engine was the benchmark, the fastest on the grid. Consequently, the FIA authorised additional homologations for Mercedes, Ferrari, Audi and Honda.
While the official FIA report was not released to the press, the outcome was confirmed by team principals and drivers, and a leaked document later corroborated the findings. The decision sparked controversy because Mercedes, whose works team had dominated the early part of the season by winning the first six Grand Prix, was now being granted an extra development slot. Red Bull, on the other hand, had managed only a single podium finish in the same period and appeared to be losing ground despite being the current engine leader.
Max Verstappen, Red Bull’s lead driver, publicly criticised the ruling, arguing that it unfairly penalised the team that had built the strongest power unit. Mercedes team principal Toto Wolff also raised questions about the FIA’s methodology, insisting that his squad possessed "the most powerful power unit" and demanding greater transparency. After the second ADUO review, which concluded with the Hungarian Grand Prix just before the summer hiatus, the FIA released a comprehensive statement covering both assessment periods. For the first period, the FIA stated: "Mercedes were determined to be within the two‑to‑four percent 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 percent behind the benchmark and will each receive two additional homologations for both 2026 and 2027, again with appropriate cost‑cap and testing adjustments." The second‑period findings delivered a further blow to Red Bull. The FIA announced that "no additional homologations were granted to any of the Power Unit Manufacturers" for the latest review window. This indicates that, according to the FIA’s data, Red Bull’s engine remained within two percent of the top‑performing unit and therefore did not qualify for extra development rights. In practical terms, Red Bull is still regarded as operating the strongest power unit on the grid, while Mercedes and the other manufacturers must wait for the next ADUO window to request further upgrades.
At the time of writing, the championship standings reflect Mercedes' early dominance. Driver Kimi Antonelli leads the pack, followed by teammate George Russell and Ferrari’s Lewis Hamilton, with a 59‑point advantage over the rest of the field.
Max Verstappen finds himself 130 points adrift of the sixth‑placed Italian driver. In the Constructors' Championship, Mercedes sit 87 points clear of Ferrari, while McLaren, which also runs a Mercedes engine, has surged into third place thanks to Lando Norris’s back‑to‑back victories. Mercedes has technically been free to implement its 2026 upgrade since the June announcement, but the team has not yet activated the new parts on track.
Ferrari, Audi and Honda are believed to have each introduced one of their two allotted upgrades for the 2026 season, with the second set slated for future deployment pending the next ADUO review. FIA single‑seater director Nikolas Tombazis emphasized the robustness of the ADUO analysis, 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 with the Dutch Grand Prix and will run through to the Mexico City Grand Prix on 1 November. Teams now have a clear timeline for when they can request further homologations, and the FIA has signalled that the process will continue to be refined as more data becomes available. Looking ahead, the next few races will be crucial for Red Bull, which must maintain its engine advantage while Mercedes and the other manufacturers seek to close the gap through their permitted upgrades.
The balance of power on the grid could shift dramatically once the next set of homologations is approved, potentially reshaping the championship battle as it heads into the final stretch of the season. Fans can follow the upcoming Italian Grand Prix at Monza, Ferrari’s home race, on 4‑6 September via Sky Sports F1, and continue to track the evolving engine development story as the sport moves toward the 2026 technical era.