Paddy Power Betfair fined after stolen cash is gambled through its website
Paddy Power Betfair has been fined £2.2m for failing to stop stolen money being gambled through its website and for failing to protect customers showing signs of problem gambling.
The Gambling Commission said the bookmaker's failings meant "significant amounts of stolen money flowed through their exchange".
One customer used money defrauded from his employer, Birmingham Dogs Home.
Paddy Power Betfair apologised and said it had strengthened its procedures.
The regulator said Paddy Power Betfair's behaviour was simply not acceptable.
A Gambling Commission investigation also found that the bookmaker failed to adequately interact with customers who were displaying signs of problem gambling.
"These failings all stem from one simple principle - operators must know their customer," said Richard Watson, Gambling Commission executive director.
"If they know their customer and ask the right questions then they place themselves in a strong position to meet their anti-money laundering and social responsibility obligations."
As part of the settlement, Paddy Power Betfair will make a £1.7m payment to GambleAware, the independent charity that commissions research, education and treatment services to reduce gambling-related harm in the UK.
Paddy Power Betfair chief executive Peter Jackson said: "We have a responsibility to intervene when our customers show signs of problem gambling. In these five cases our interventions were not effective and we are very sorry that this occurred.
"In recent years, we have invested in an extensive programme of work to strengthen our resources and systems in responsible gambling and customer protection. We are encouraged that the Gambling Commission has recognised significant improvement since the time of these cases in 2016."
The commission's inquiry centred on five customers in 2016, including two who were allowed to gamble stolen money - one of whom had defrauded his employer, Birmingham Dogs Home.
Simon Price, who was chief executive of the dogs home, and his wife Alayna admitted cheating the charity of £894,754 to fund his gambling addiction.
Mr Price was jailed for five years at the end of 2017, while Mrs Price was given a two-year suspended term.
As part of Paddy Power's settlement with the Gambling Commission, the money will be returned to the dogs home.
Shares in Paddy Power Betfair rose 3.4% in late trading in London.