McLaren Racing CEO Zak Brown wrote to FIA President Mohammed Ben Sulayem requesting rule changes that would prohibit common ownership structures across multiple Formula 1 teams, according to published correspondence. The letter follows months of quiet concern among team principals about potential conflicts as the grid debates expansion beyond ten teams and $200 million anti-dilution payments loom for existing constructors.

Brown's letter did not name specific ownership groups but arrives as several entities with existing motorsport portfolios have circled F1 grid slots. The timing matters: Andretti Global's stalled entry bid, backed by General Motors and Cadillac branding, remains in negotiation with Formula One Management, while Red Bull operates two teams under a single corporate parent—albeit with distinct ownership structures predating current governance frameworks. Brown's proposal would close future loopholes, not unwind existing arrangements.

The competitive integrity argument centers on data flow and technical collaboration. Formula 1's Concorde Agreement permits customer power unit supply and limited gearbox partnerships, but strictly prohibits shared aerodynamic development or wind tunnel access between teams. Brown's concern is structural: if a single entity owns two teams outright, enforcement becomes theater. The $145 million budget cap relies on team-level accounting segregation; common ownership creates reporting fungibility that auditors can challenge but rarely disprove. One team principal, speaking off-record at the Las Vegas paddock in November, noted that even separate management structures cannot prevent portfolio-level resource allocation decisions that favor one team's championship bid over another's.

The commercial stakes are sharper than the sporting ones. F1's current ten-team structure splits $1.15 billion in annual prize money, with constructor standings determining payout tiers. An eleventh team dilutes each existing share by roughly 9 percent unless the commercial pie grows proportionally—unlikely given Liberty Media's focus on margin expansion over top-line growth. Brown's governance push doubles as financial defense: if multi-team ownership becomes standard, large conglomerates with deep balance sheets could operate junior and senior squads, extracting two revenue shares while consolidating development spend. McLaren, privately held and running one team, cannot match that structural leverage.

Brown has form here. He led the push for cost cap enforcement in 2021, publicly naming Red Bull after their $1.8 million breach, and has consistently advocated for tighter governance as team valuations rise. Aston Martin sold a 24 percent stake in October 2023 at a $2.3 billion enterprise valuation; McLaren itself is rumored to be in early talks with Middle Eastern sovereign wealth funds about minority investment. Those buyers want clarity on competitive structure before writing nine-figure checks.

The FIA's response timeline is unclear, but three events will surface the league's position. First, the Andretti decision, expected before the March 2025 Bahrain season opener, will either green-light an eleventh team or codify the ten-team cap indefinitely. Second, the next Concorde Agreement negotiation window opens in 2026, when governance frameworks can be rewritten. Third, watch personnel movement between Red Bull Racing and RB—formerly AlphaTauri—during the off-season; any senior technical hires crossing teams will reignite the collaboration debate and give Brown's letter fresh legs.

Brown's letter is already public, which means the ask was designed for visibility as much as policy. The FIA receives hundreds of team submissions annually; McLaren chose to let this one circulate. That signals confidence in paddock support or, alternatively, a willingness to stand alone if it means protecting McLaren's one-team model from obsolescence.