The Office of Competition and Consumer Protection (UOKiK) in Poland initiated proceedings against T-Mobile’s local unit over false advertising claims, which can result in a fine of up to 10 per cent of its annual revenue.

In a statement, the head of the regulatory body, Tomasz Chrostny, explained T-Mobile’s slogan of “1200GB free for a year” can potentially misinform customers as the actual package consists of 100GB data a month for a maximum of 12 months, which the user has to renew periodically for PLN35 ($7.89) each time.

The regulator also stated details of the package deal in both online and outdoor advertising “remain almost invisible, written in a dozen times smaller font”, with Chrostny adding the ads suggest “a one-time data package of 1200GB and not a dozen or so smaller packages”.

UOKiK stated T-Mobile Poland had received a soft notice, but no significant change has been made to its advertising approach.

In a response to the allegations, T-Mobile Poland stated its commercial slogan was well received by customers but added it is ready to “provide UOKiK with materials related to the promotion of the offer”.

UOKiK said T-Mobile will be on the hook for “a penalty of up to 10 per cent turnover”, if the allegations are confirmed.