Cape Town - Bath have been fined £60 000 (R1 million) for allowing Wales’ number eight Taulupe Faletau to play against South Africa in the November internationals.
Premiership Rugby have imposed strict guidelines when it comes to overseas players representing their country outside of the agreed international window.
Northampton were punished for the same offence in 2013 after Saints’ wing George North featured for Warren Gatland’s men.
A Premiership Rugby spokesperson said: "This board policy has been an essential one, especially as there has been an increasing number of international matches being organised outside the specified international weeks. The agreed policy is well known to clubs, players and unions."
The fine was reduced from £90 000 due to Bath’s co-operation with the process and Tarquin McDonald, chief executive of the West Countrymen, said: "We understand Premiership Rugby’s position on this and have subsequently worked proactively with them to swiftly achieve a fair resolution.
"We believed this situation would change, that has not yet happened and we have therefore come to an appropriate settlement with Premiership Rugby.
"However, we continue to believe that there is appetite for change and that this on-going conflict between the club and international calendars is not good for players, clubs or unions.
"We continue to support the objective of a solution for the separation of club and international calendars in a way which benefits players, clubs and unions, and brings an end to situations such as this."