Homegrown player sales: The clubs to make the most profit since 2015
CIES Football Observatory has calculated how much clubs around the world have made by selling home-grown players developed in their youth ranks in recent years.
Youth academies can often be the lifeblood of a club, producing players they then sell for a handsome transfer fee to reinvest back in their squad. But even the biggest teams can still make considerable money simply from investing time in developing young talents.
For a player to be considered 'home-grown', they must have spent at least three years at a club between their 15th and 21st birthdays.
The fees include all add-ons and the list covers every transfer registered since the start of the 2015 summer transfer window.
Before getting onto the top 25 selling clubs, here's a look at selected others who didn't make the list: Tottenham (€108m), Roma (€82m), Borussia Dortmund (€81m), Leicester (€74m), Bayern Munich (€73m), Juventus (€72m), Inter (€66m), AC Milan (€65m), Manchester United (€60m)
25. Paris Saint-Germain - €117m
Biggest sale: Moussa Diaby to Bayer Leverkusen (€15m)
24. Fiorentina - €122m
Biggest sale: Federico Chiesa to Juventus (€50m)
23. Aston Villa - €132m
Biggest sale: Jack Grealish to Manchester City (€117m)
22. Dinamo Zagreb - €135m
Biggest sale: Dani Olmo to RB Leipzig (€41m)
21. Porto - €136m
Biggest sale: Fabio Silva to Wolves (€39m)
20. Schalke - €136m
Biggest sale: Leroy Sane to Manchester City (€52m)
19. Arsenal - €139m
Biggest sale: Alex Iwobi to Everton (€43m)
18. Red Bull Salzburg - €140m
Biggest sale: Patson Daka to Leicester (€29m)
17. Manchester City - €145m
Biggest sale: Kelechi Iheanacho to Leicester (€28m)
16. PSV Eindhoven - €146m
Biggest sale: Memphis Depay to Manchester United (€37m)
15. Anderlecht - €147m
Biggest sale: Jeremy Doku to Rennes (€29m)
14. Athletic Club - €148m
Biggest sale: Kepa Arrizabalaga to Chelsea (€80m)
13. Flamengo - €152m
Biggest sale: Vinicius Junior to Real Madrid (€45m)
12. Barcelona - €161m
Biggest sale: Pedro to Chelsea (€29m)
11. Atletico Madrid - €167m
Biggest sale: Lucas Hernandez to Bayern Munich (€80m)
10. Liverpool - €171m
Biggest sale: Raheem Sterling to Manchester City (€70m)
9. Sporting CP - €209m
Biggest sale: Joao Mario to Inter (€46m)
8. Chelsea - €210m
Biggest sale: Tammy Abraham to Roma (€44m)
7. Atalanta - €211m
Biggest sale: Amad Diallo to Manchester United (€40m)
6. Bayer Leverkusen - €213m
Biggest sale: Kai Havertz to Chelsea (€100m)
5. Lyon - €270m
Biggest sale: Alexandre Lacazette to Arsenal (€59m)
4. Ajax - €283m
Biggest sale: Matthijs de Ligt to Juventus (€85m)
3. Monaco - €285m
Biggest sale: Kylian Mbappe to PSG (€180m)
2. Real Madrid - €330m
Biggest sale: Alvaro Morata to Chelsea (€79m)
1. Benfica - €379m
Biggest sale: Joao Felix to Atletico Madrid (€121m)
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