UK-listed online gambling operator GVC Holdings is putting aside €200m as a provision against a hefty back-tax demand from the Greek government.

On Thursday, GVC announced that it had received a tax audit assessment from the Greek Audit Center for Large Enterprises, which is demanding €186.77m in back taxes to cover a GVC subsidiary’s activity in the Greek market for the years 2010 and 2011.

The GVC subsidiary in question was owned during the period by Sportingbet, whose operations GVC acquired in 2013 as part of a joint deal with rival bookmaker William Hill. At the time, Sportingbet held an interim Greek license, the permanent replacements for which have been still not been issued by Greek authorities.

GVC says the nine-figure back-tax demand is “substantially higher by multiples of the total Greek revenues generated” by Sportingbet during the period in question. GVC disputed the Greek taxman’s methodology for arriving at this “widely exaggerated” figure, while noting that “multiple other online gaming operators” had been subjected to similar demands.