More deaths could occur unless the parent company of the betting exchange Betfair does more to protect customers, the coroner in the gambling-related suicide of Luke Ashton has warned.

Ivan Cartwright said Flutter Entertainment’s controls “were and are inadequate” to protect people with a gambling problem. He accused the company of doing only what was necessary to meet regulatory requirements, rather that following best practice to prevent harm. Flutter has 56 days to respond.

Cartwright issued the warning in a letter to Flutter’s chief executive, Peter Jackson, who has been paid £11.3m over the past two years. He also copied the letter to the Gambling Commission and to the culture secretary, Lucy Frazer, who is overseeing government proposals to reform gambling regulation.

Last month the Leicestershire coroner issued a landmark ruling in the 2021 suicide of Luke Ashton, who took his own life after a period of addiction during which he placed up to 100 bets a day online and racked up £18,000 in debts.

The ruling, in which gambling disorder was determined to be a factor in Ashton’s death, is believed to be the first of its kind.

In a conclusion to accompany the verdict, issued last month, Cartwright said Betfair, which gave Ashton £5 “free bet” offers, had failed to “interact or intervene with Luke in any meaningful way” in the period leading up to his death.

Flutter, the £28bn international gambling firm that owns Betfair, says it has significantly improved its safer gambling measures since then.

But on Wednesday, in his letter to Jackson, Cartwright said he believed there was still a risk of future deaths due to “inadequate” safeguards.

He said: “In my opinion there is a risk that future deaths could occur unless action is taken. In the circumstances it is my statutory duty to report to you.”

Cartwright said the company’s safer gambling tools “do not amount to any meaningful interaction” with customers who may be showing signs of addiction.

Cartwright said algorithms designed by Flutter to flag up customers gambling excessively appeared to have failed because they judged Ashton’s gambling not to be “exceptional”, despite an increase in his playing time, deposits and losses.

He added that Betfair “appears to judge the extent of its responsibilities to gambling customers solely with regard to industry (regulatory) standards, rather than current good or best practice”.

Flutter, which also owns Paddy Power and Sky Betting & Gaming, said it would respond formally.

The company said it had made “significant changes to our controls since 2021 and will, of course, incorporate additional learnings from this tragic case into our systems and processes.

“We wish to reiterate our sincere condolences to Mrs Ashton and her family. We are truly sorry for their loss.”

Ashton was a member of a Betfair “rewards” scheme whose members were eligible for a £5 “free” bet each month.

The Gambling Commission said it was reviewing such incentives, as part of the government’s white paper on gambling reform.

But the Commission will take no further action against Flutter. This is because Ashton’s gambling took place while the company was in “special measures” triggered by separate incidents, which the regulator said had already led to the company improving its controls and paying a £635,000 penalty.

The Guardian has approached the Department for Culture, Media and Sport for comment.

• In the UK and Ireland, Samaritans can be contacted on freephone 116 123, or email jo@samaritans.org or jo@samaritans.ie. In the US, you can call or text the National Suicide Prevention Lifeline on 988, chat on 988lifeline.org, or text HOME to 741741 to connect with a crisis counselor. In Australia, the crisis support service Lifeline is 13 11 14. Other international helplines can be found at befrienders.org