Hussain Patel, the son of multi-millionaire Arif Patel, bought the 6.53% stake in the city's football club, from former chief executive Steve Jackson in a deal worth more than £300,000.
The deal makes the Lancaster Royal Grammar School student, the club's fourth-largest shareholder.
Chairman Derek Shaw, said: "We welcome the Patel family.
"I have know Arif for 30 years as a shareholder, and he has many successful local businesses.