The HMRC investigation first came to light in November 2019 with the authorities asking for information regarding the Turkish-facing business Entain held between 2011 and 2017.
At that time Entain understood HMRC’s investigation was directed at a number of former third-party suppliers, relating to the processing of payments for online betting and gaming in Turkey.
However, in 2020 it was announced that HMRC was widening the scope of its investigation and was examining potential corporate offending within the group.
Entain told the City on Wednesday that it was in "deferred prosecution agreement" negotiations with the Crown Prosecution Service (CPS) – under which a prosecution is suspended provided an organisation meets certain specified conditions – and was working towards achieving a resolution of the ongoing HMRC investigation.
It added: "While the company cannot say at this stage what the consequences of the investigation will be, it is likely that they will include a substantial financial penalty which is yet to be determined. The company cannot identify reliably at this stage the size of any financial penalty."