About £20m could be repaid to retailers if the Copyright Tribunal's decision to cap fees on music played in stores is upheld.

The Tribunal ruled that tariff increases introduced in 2005 by the Public Phonographic Ltd (PPL) were "excessive" and has placed a 10% limit on the rises.

The PPL, which collects royalties on behalf of recording companies, will also have to repay all of the additional fees paid by retailers since 2005 unless it is successful in appealing the decision.

The charges were introduced for stores with a floor space of more than 1,000sq ft in which a TV or radio was played, and increased in proportion with shopfloor size, which in some cases led to tariff increases of up to 192%.

If the decision is upheld, individual stores will only have to pay a maximum of £110. Stores under 1,000sq ft will still have to pay the flat rate of £100 per year.

All stores which play music still have to pay for a separate Performing Right Society licence for royalties to songwriters and composers.