(Bloomberg) -- Bank of New York Mellon Corp. and a financial technology company are going back to a Canadian court in a long-running legal dispute over the New York-based firm’s alleged misuse of data it licensed. 

BNY Mellon and SS&C Technologies Holdings Inc. have been embroiled in a yearslong legal tussle, after SS&C discovered information that led it to believe BNY had taken financial-markets data and shared it with dozens of other entities, without authorization or paying additional fees. 

SS&C sued, alleging that BNY Mellon and its Canadian joint venture, CIBC Mellon Global Securities Services Co., had breached the terms of their contracts. In 2021, it won a finding of liability from the Ontario Superior Court, but the judge awarded only minimal damages.

SS&C is now appealing, saying the court erred in its calculation and that it’s owed as much as $889.8 million. 

The judge “resorted to guesswork that was inconsistent with his previous factual findings in the liability decision” in the ruling on damages, SS&C said in a notice of appeal filed Feb. 1 at the Court of Appeal for Ontario. BNY Mellon “destroyed and refused to produce relevant evidence” that would have established how it used market data provided by SS&C, the appeal said.  

Through a spokesperson, BNY Mellon declined to comment because the litigation is ongoing. The firm has also appealed the finding of liability. 

SS&C is a public company based in Windsor, Connecticut. It provides operations services to investment managers, such as trade-order management, performance reporting, accounting and compliance.  

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