Mr Green Ltd, a subsidiary of MRG, has been fined €312,000 ($361,000) by the Netherlands Gaming Authority (KSA).
The fine relates to a failure to prevent Dutch players from gambling on its websites and allegedly failing to use IP blocking technology under the ‘prioritisation’ criteria.
Mr Green is set to appeal the fine, arguing that most gaming operators in the Netherlands do not use IP blocking on their sites.
According to MRG, the Dutch market represents 6% of the company’s total revenue and amounted to SEK 26m ($2.8m) in the second quarter of this year.
Last month, the KSA also fined Betsson subsidiary Corona €300,000 for operating in the Netherlands without a license, although Betsson has said it will appeal the decision.