The Fédération Internationale de l'Automobile (FIA) has officially confirmed that Mercedes has been permitted to introduce upgrades to its power unit, despite vocal objections from rival teams, most notably Red Bull. 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 season.
The ADUO system is intended to give manufacturers a structured pathway to close any performance gap they may have relative to the leading power unit as the regulatory cycle progresses. In June, after the first performance review covering the opening five Grand Prix events, the FIA disclosed that Red Bull's engine was judged to be the benchmark for the season. Consequently, Mercedes, Ferrari, Audi and Honda were each allocated additional development slots. While the FIA did not publish the detailed analysis, team principals and drivers confirmed the outcomes publicly, and a leaked document later corroborated the findings.
The ruling sparked controversy across the paddock. Mercedes, whose works team had dominated the early calendar by winning the first six races, appeared to receive a technical advantage, whereas Red Bull, which had managed only a single podium finish in the same period, seemed poised to fall further behind. Red Bull driver Max Verstappen publicly criticised the decision, arguing that it penalised a team that had already demonstrated strong performance.
Meanwhile, Mercedes team principal Toto Wolff questioned the transparency of the FIA's methodology, noting in July that his outfit possessed "the most powerful power unit" on the grid. After a period of quiet while the FIA reviewed the second set of data, the organization released a comprehensive statement following the Hungarian Grand Prix, which marked the end of the summer break. The statement confirmed the earlier June findings for the first assessment period and added new information for the second period.
For the initial period, Mercedes was found to be operating within a two‑to‑four‑percent performance window behind the leading unit, granting them one additional homologation for 2026 and another for 2027, along with corresponding increases to their cost‑cap allocation and dyno‑testing allowances. Audi, Ferrari and Honda were assessed as being more than four percent off the pace, earning them two extra homologations for each of the next two seasons, together with proportionate cost‑cap and testing allowances. The second‑period review, however, delivered a less favorable outcome for Red Bull. The FIA announced that no further homologations would be awarded to any power‑unit manufacturer for the upcoming period.
This implies that Red Bull's engine remained within two percent of the best unit on the grid, effectively confirming its status as the top‑performing power unit at that stage of the season. Had any of the other manufacturers improved sufficiently since June to surpass Red Bull, the British team would have qualified for its own upgrade, but the data did not support that scenario.
Current championship standings underscore the competitive stakes. Mercedes driver Kimi Antonelli leads the drivers' leaderboard, followed by teammate George Russell and Ferrari's Lewis Hamilton, who sit 59 points behind the leader.
Max Verstappen trails by 130 points, occupying sixth place. In the constructors' championship, Mercedes enjoys an 87‑point lead over Ferrari, while McLaren, which also runs a Mercedes engine, has surged into third place thanks to Lando Norris's recent victories. Although Mercedes has been authorised to implement its 2026 upgrade since the June announcement, the team has 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 2026 season, with the second set of upgrades still pending.
FIA single‑seater director Nikolas Tombazis emphasized the rigor of the ADUO review process, stating that the analysis was "thorough and exhaustive" and that the organisation has a high degree of confidence in its conclusions. He also highlighted the need to protect the confidentiality and intellectual property of the teams involved, noting that the ADUO framework is in its inaugural year and may evolve through ongoing dialogue with power‑unit manufacturers. The third ADUO review window commenced at the Dutch Grand Prix and will run through to the Mexico City Grand Prix on November 1. As the season progresses toward its climax, the impact of these development allowances will be closely watched, particularly as teams balance the benefits of additional upgrades against the constraints of the cost cap and the strategic timing of introducing new components.
Looking ahead, Formula 1 will travel to Monza for the Italian Grand Prix, Ferrari's home race, on September 4‑6, where the interplay of engine performance, upgrade strategies, and championship pressures will likely produce another dramatic chapter in the 2026 campaign.