The France U21 international signed a five-and-a-half-year deal with the Premier League leaders in January and in doing so helped his first club Sporting Union Agen Football to avoid falling into administration.
Laporte started his career with the club, who are based in his home town, before eventualy moving to Spain via Aviron Bayonnais.
Due to FIFA rules on the development of players, Agen were eligible for 0.25% of the fee for every year he spent at the club between the ages of 12 and 16, leading the eighth-tier French side to receive a windfall of 1% of the total transfer fee, a princely £570,000.
Agen's staff were understandably delighted by the unexpcted boost, with co-president Jean-Claude Brunel telling Spanish publication 'El Correo': "Fate knocks at our door. It is unexpected and a beautiful reward for our efforts.
"If the ruling had not been manifested, we were determined to close at the end of the season as we were unable to meet the operating costs."