LIVERPOOL -- Inter Milan would miss out on a huge financial windfall should Philippe Coutinho leave Liverpool for Barcelona, a source has told ESPN FC.
The source said that Inter did not include a sell-on clause when they sold Coutinho to Liverpool in January 2013.
The Brazil international is attempting to force a move to Barcelona by handing in a transfer request after Liverpool rejected two offers -- worth £72 million and £90m -- from the Catalan side.
Inter believe they are only in line to receive a very small percentage of any transfer fee, if Coutinho completes a move to a club in another country, under FIFA's solidarity mechanism.
Article 21 of the FIFA Regulations on the Status and Transfer of Players states: "If a professional is transferred before the expiry of his contract, any club that has contributed to his education and training shall receive a proportion of the compensation paid to his former club [solidarity contribution]."
The solidarity payment amounts to just five percent of the agreed transfer fee.
The buying club withholds the five percent of the fee and then distributes it among clubs who qualify for payment, which in Coutinho's case would be Inter and Vasco da Gama, where the 25-year-old began his footballing career. That means Inter would be due around just €3m if Coutinho were to join Barcelona in a €120m deal.
FIFA regulations read: "This solidarity contribution reflects the number of years [calculated pro rata if less than one year] he was registered with the relevant club[s] between the seasons of his 12th and 23rd birthdays."
Coutinho spent his formative years in Brazil with Vasco and then became an Inter player at the age of 16, before switching to Liverpool as a 20-year-old.
If Coutinho were to move, the full five percent would not be allocated between Inter and Vasco, with Liverpool having the player on their books at the age of 20.
"In reality, the full five percent is rarely allocated, so in this case Liverpool would get that part of the pot," sports lawyer Dan Chapman told ESPN FC.
"In the transfer agreement, the clubs -- if they have the time -- can work out and agree who is paid what, and therefore five percent is not withheld, just the right amount.
"Or the buying club withholds the five percent and then works out who is due money and pays it. Then the shortfall not paid out eventually goes to the selling club."
In January, Inter's sporting director Piero Ausilio told ESPN FC that selling the playmaker for £8.5m was "perhaps one of my greatest regrets in over 20 years" at the Italian club.
"I believe there are many clubs in England, Scotland and Ireland that are owed money," Chapman added. "Not big sums, but money that could make a difference to them.
"Yet they do not realise they have a claim and the system does not always ensure they are paid. There are some small or non-league clubs who could well be owed £50,000 here or there that they do not realise.
"The system also produces some odd results. A feature of the Paul Pogba transfer that I have not seen anyone discuss is that Manchester United were due a solidarity payment from Juventus for the years they had him, even though they were the ones paying the transfer fee to Juventus."