The penalty related to an “extended period” of 220.2 million transaction reports between November 2007 and March 2017.

Mark Steward, FCA executive director of enforcement and market oversight said: “The failings in this case demonstrate a failure over an extended period to manage and test controls that are vitally important to the integrity of our markets.

“These were serious and prolonged failures.

“We expect all firms will take this opportunity to ensure they can fully detail their activity and are regularly checking their systems so any problems are detected and remedied promptly, unlike in this case.”

The FCA said accurate and complete transaction reporting helps underwrite market integrity and supervise firms and markets.

In particular, transaction reports help the FCA identify potential instances of market abuse and combat financial crime.

GSI failed to ensure it provided complete, accurate and timely information in relation to approximately 213.6m reportable transactions.

It also erroneously reported 6.6m transactions to the FCA, which were not, in fact, reportable.

Altogether, over a period of nine and a half years, GSI made 220.2m errors in its transaction reporting, breaching FCA rules.

The FCA also found that GSI failed to take reasonable care to organise and control its affairs responsibly and effectively in respect of its transaction reporting.

These failings related to aspects of GSI’s change management processes, its maintenance of the counterparty reference data used in its reporting and how it tested whether all the transactions it reported to the FCA were accurate and complete. 

GSI agreed to resolve the case and so qualified for a 30% discount in the overall penalty.

Without this discount, the FCA would have imposed a financial penalty of £49,063,900.