League Two Luton will receive at least £1.1m in sell-on fees from Andre Gray's £9m move to Burnley from Brentford.
The 24-year-old moved to Kenilworth Road in 2012 and left for Brentford for a reported £500,000 last summer.
Striker Gray scored 18 goals as the Bees reached the Championship play-offs last term, leading Burnley to pay a club-record fee for him.
Luton will receive £1.1m spread over three seasons, and a further £700,000 if he helps the Clarets win promotion.
Hatters chief executive Gary Sweet told the club website: "Everyone at the club takes huge pride in seeing players who have developed with us blossom in their careers.
"We're absolutely thrilled for Andre in this case - he's a very honest, ambitious and hard-working player who deserves every success.
"We would also like to personally thank those people who played their part in the scouting and recruitment process of Andre, as well as those who have helped develop him into the player he now is."
Meanwhile, Luton's 20-year-old striker Jack Marriott has signed a contract to keep him at Kenilworth Road until the summer of 2017, with the option of extending to 2019.