Private investment firm Arctos Partners has acquired an unconfirmed percentage in AMR Holdings GP Limited, the team's holding company, with the deal expected to close by the end of the year.
Arctos already has a stake in Major League Baseball team, Boston Red Sox, and the Fenway Sports Group, owner of the English Premier League club Liverpool.
Following the arrival of Arctos, The Financial Times has now placed the valuation of the team at $1bn.
Stroll could part with further equity in the future as title partner Aramco, Saudi Arabia's biggest gas and petroleum company, has an option in its deal with the team to purchase a 10 percent stake.
Arctos' arrival would appear to allay fears Stroll could, at some point in the near future, decide to sell the team following recent speculation.
Managing director Doc O'Connor has stated that he sees his company's investment as “the beginning of a long-term partnership with Lawrence and the entire organisation.”
He added: “This investment is consistent with our firm's strategy, which focuses on backing leading sports brands across North America and Europe.
“We will provide extensive resources to enhance the team's reach and brand, including industry intelligence sourced from our proprietary quantitative research and data science platform.
“The team is a leading name in Formula 1, one of the fastest-growing sports in the US, and we are truly excited to be entering the sport alongside Lawrence and his team.”
Welcoming his new minority investor, Stroll said: “As investors in several leading sports franchises, Arctos brings deep industry knowledge, and I am thrilled that Aston Martin will be joining such a prestigious portfolio.
“The team has enjoyed tremendous success this season with eight podium finishes and our biggest points haul as a team, but our collective ambition is greater.
“Arctos sees the potential and value of this project as we continue to build a world-class Formula 1 team.
“They share our vision for our ultra-luxury brand, and they are extremely passionate about the sport and its prospects.
“We are investing in infrastructure, people, and processes, and this is the perfect time to add strength in depth with the operational expertise and strategic experience of Arctos.
“Together, we will continue to drive this team forward and build an even brighter and successful future.”
Earlier this year, Alpine sold a 24% stake in its F1 team to an investment group consortium – which included actors and Wrexham AFC owners Ryan Reynolds and Rob McElhenney – leading to a valuation of US$900 million (AU$1.4m).