Merrill Lynch International has been fined £13,285,900 for transaction reporting failures.

The UK's Financial Conduct Authority has fined Merrill Lynch International £13.28 million ($19.96 million) for incorrectly reporting over 35 million transactions and failing to report another 121,387 at all over a seven-year period.

The fine is the largest imposed yet for transaction reporting failures. The watchdog said the failings, which occurred between 2007 and 2014, came in spite of a private warning it had issued Merrill Lynch back in 2002, as well as a £150,000 fine it had imposed in 2006.

“Proper transaction reporting really matters. Merrill Lynch International has failed to get this right again – despite a private warning, a previous fine, and extensive FCA guidance and enforcement action in this area,” said the FCA's acting director of enforcement and market oversight, Georgina Philippou.

“The size of the fine sends a clear message that we expect to be heard and understood across the industry. Accurate and timely reporting of transactions is crucial for us to perform effective surveillance for insider trading and market manipulation in support of our objective to ensure that markets work well and with integrity.”

Without the 30 per cent discount it received for settling at an early stage of the investigation, Merrill Lynch International would have had to fork out a total of £18,979,876.