Manchester United, who are eyeing a possible sum if Inter Milan sell Romelu Lukaku to Chelsea. According to the Telegraph, the Blues have hope they can land their former Belgian striker for £100m.United are said to have agreed to get a 5% cut on Lukaku's next transfer, meaning they would be entitled to £5m if he returns to Stamford Bridge.
But what about the other times clubs have made big profits from a sell-on clause?Here, Daily Star Sport takes a look at seven of the biggest sell-on fees in transfer history....
When the Red Devils made the statement signing of Jadon Sancho this summer, neighbours Manchester City earned a significant windfall.That is because of the 15% sell-on clause they agreed with Borussia Dortmund when selling.
Read more on dailystar.co.uk