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)

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Biggest sale: Moussa Diaby to Bayer Leverkusen (€15m)

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Biggest sale: Federico Chiesa to Juventus (€50m)

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Biggest sale: Jack Grealish to Manchester City (€117m)

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Biggest sale: Dani Olmo to RB Leipzig (€41m)

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Biggest sale: Fabio Silva to Wolves (€39m)

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Biggest sale: Leroy Sane to Manchester City (€52m)

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Biggest sale: Alex Iwobi to Everton (€43m)

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Biggest sale: Patson Daka to Leicester (€29m)

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Biggest sale: Kelechi Iheanacho to Leicester (€28m)

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Biggest sale: Memphis Depay to Manchester United (€37m)

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Biggest sale: Jeremy Doku to Rennes (€29m)

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Biggest sale: Kepa Arrizabalaga to Chelsea (€80m)

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Biggest sale: Vinicius Junior to Real Madrid (€45m)

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Biggest sale: Pedro to Chelsea (€29m)

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Biggest sale: Lucas Hernandez to Bayern Munich (€80m)

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Biggest sale: Raheem Sterling to Manchester City (€70m)

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Biggest sale: Joao Mario to Inter (€46m)

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Biggest sale: Tammy Abraham to Roma (€44m)

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Biggest sale: Amad Diallo to Manchester United (€40m)

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Biggest sale: Kai Havertz to Chelsea (€100m)

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Biggest sale: Alexandre Lacazette to Arsenal (€59m)

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Biggest sale: Matthijs de Ligt to Juventus (€85m)

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Biggest sale: Kylian Mbappe to PSG (€180m)

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Biggest sale: Alvaro Morata to Chelsea (€79m)

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Biggest sale: Joao Felix to Atletico Madrid (€121m)

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