The FIA has received several entry requests to expand the grid beyond the current 10 teams.
Michael Andretti's high-profile bid is believed to be close to being approved by the governing body. But Andretti is still facing fierce resistance from F1, which will also have to approve any entry, and the majority of the teams due to concerns over their prize fund being diluted.
Speaking to Motorsport.com and Autosport's sister website Motorsport-Total, McLaren chief Brown believes that, provided the current $200m anti-dilution fee is at least tripled in the next Concorde Agreement from 2026, a viable expansion team could be financially beneficial for the existing outfits.
When asked why he would support an 11th team diluting the prize money, Brown replied: "Because I believe I'm not giving up that money.
"It has to be the right team with the right resources. Let's assume for a moment it is. If they pay the right franchise fee - which is not 200 million, let's say it's 700 million - then I get 70 million.
"The dilution of an 11th team is about 10 million a year. So, if I get 70, it will be covering me for seven years.
"Then if it costs 700 just to enter, it's created 700 million more in franchise value. So, whatever I'm worth today, pick a number... two billion, now I'm worth 2.7 billion.
Source: Autosport