Canadian businessman Michael Latifi, whose son Nicholas currently races in Formula Two, has bought a stake of around 10 percent in the McLaren Group that includes the Formula One team.
McLaren, announcing Latifi's involvement, said the 394 million dollar capital injection "significantly strengthens the group's balance sheet and underpins its ambitious growth plans".
The proceeds will be received over the coming year.
The McLaren Group includes the McLaren Automotive sportscar business, McLaren Racing and McLaren Applied Technologies companies.
The shareholding, through Latifi's British Virgin Islands-based company Nidala Ltd, was seen as a purely commercial deal and the team said it was unrelated to the 22-year-old Latifi's racing career.
Latifi senior, who runs Canada's Sofina Foods Inc., said in a statement he had been an admirer of the McLaren brand and businesses for some time.
"McLaren is a unique organisation in automotive, racing and technology with exciting long-term growth prospects, which is why I have made this investment," he added.
Bahrain's Mumtalakat holding company remains the majority shareholder in McLaren, with a 56 percent stake, followed by the TAG Group led by Saudi-born businessman Mansour Ojjeh which has 14 percent.
There are also four smaller shareholders.
McLaren announced last year, when the British-based company was valued at 4.6 billion dollars, that the group had agreed to buy the stake held by ousted chief executive Ron Dennis.
Latifi is the first significant new shareholder since Dennis's departure.
McLaren have not won a grand prix since 2012 but have moved up the standings since they ended a failed three-year partnership with Honda at the end of 2017.
Now with Renault engines, they are fifth in the championship ahead of this weekend's showcase Monaco Grand Prix.
Nicholas Latifi is ninth in the F2 standings and is also a development driver for the Mercedes-powered Force India F1 team.
McLaren currently have Spain's double world champion Fernando Alonso and Belgian Stoffel Vandoorne as race drivers with Britain's Lando Norris, the F2 championship leader, as reserve.
Lance Stroll, whose father is also one of Canada's richest men, is the country's only driver on the F1 grid at present and races for the Williams team.