McLaren Racing CEO Zak Brown sent a formal letter to FIA President Mohammed Ben Sulayem requesting rule changes that would prohibit any single entity from owning stakes in multiple Formula 1 teams. The timing arrives three months after Audi finalized its takeover of Sauber and six weeks before the FIA's next World Motor Sport Council meeting in Paris.

Brown's letter does not name specific transactions but references "future common ownership structures" that could compromise competitive integrity. The concern centers on technical information flow between teams under shared ownership, particularly during concurrent development cycles when aerodynamic concepts and suspension geometry solutions move fastest through the paddock. Formula 1's existing regulations permit manufacturers to own teams outright—Mercedes, Ferrari, Alpine, Audi from 2026—but contain no explicit prohibition on a single investment vehicle holding minority or controlling stakes across multiple constructors.

The business case for the letter is straightforward. McLaren holds no manufacturer backstop and competes as an independent against factory-backed operations with $400M-plus annual budgets when capitalized R&D is included. If a private equity platform or sovereign fund were to acquire positions in two midfield teams—say, Haas and Williams—it could theoretically pool technical staff during the off-season or synchronize wind tunnel time to exploit loopholes in the $135M cost cap. Brown's position is that the FIA should close the gap now, before a transaction tests the boundaries.

Two precedents inform the request. NASCAR banned multi-team ownership by a single principal in 2002 after Ray Evernham attempted to partner with Bill Davis Racing while running his own operation. The FIA itself prohibited Ligier and Larrousse from sharing technical resources in 1992 despite common Renault engine supply. Brown is asking for a prophylactic rule rather than adjudicating after the fact.

The counterargument runs through teams currently hunting capital. Williams Racing has been in sale rumors since the Dorilton acquisition in 2020; sources close to the family office say they would entertain a structured exit if a credible buyer emerged at a $1.5B valuation. Haas has explored minority investment from at least two U.S.-based funds in the past 18 months. If the same institutional allocator wanted exposure to both, a multi-team prohibition forecloses the strategy and potentially narrows the buyer pool.

Brown's timing also shadows the Andretti stalemate. Andretti Global applied for an 11th team slot in 2023 and received FIA approval but was blocked by Formula One Management, which argued that a new entrant must add value beyond the $200M anti-dilution fee. Michael Andretti subsequently stepped back from day-to-day negotiations in favor of his business partner Dan Towriss, CEO of Group 1001, while Cadillac formalized its powertrain partnership. If Andretti were instead to acquire an existing team outright—Sauber was rumored before the Audi deal—the ownership question becomes moot. But if Andretti wanted to enter *and* retain a stake in another series team under a different brand, Brown's proposed rule would block it.

FIA governance moves slowly. The World Motor Sport Council meets four times per year; amendments to the International Sporting Code require a simple majority but typically pass through working groups first. If Brown's letter lands on the March agenda, a vote could happen in June, with any rule effective for the 2026 season when Audi enters and the next Concorde Agreement comes up for discussion.

McLaren's own structure is worth noting. Brown operates under a 35% minority stake held by MSP Sports Capital since 2020, with Bahrain's Mumtalakat Holding retaining majority control. MSP also owns stakes in McLaren's IndyCar and Extreme E operations but no other F1 entities. The letter does not propose restrictions on private equity ownership per se—only on cross-team holdings that could create technical coordination.

The next visible signal will be whether other team principals co-sign. Toto Wolff at Mercedes and Christian Horner at Red Bull have historically opposed measures that empower independents but may support an ownership firewall if it prevents a well-funded competitor from scaling through portfolio strategy. Fred Vasseur at Ferrari has said nothing publicly. If Brown's letter remains a solo effort, the FIA may table it. If three or four principals add their names, it moves to the Council floor.

Watch for FIA working group minutes in early March and whether any team—particularly Williams or Haas—issues a public response. Also watch Andretti's next move: if Towriss announces a team purchase rather than a grid expansion, Brown's letter becomes immediately material.