A company called CPP had been fined £10.5 million for misselling insurance policies that cover the risk of cards being lost or stolen, and/or the risk of identity theft.
In many cases, these policies were partly or entirely worthless as they simply duplicated protection the customer already had from their bank. CPP will also have to pay up to £14.5 million in compensation to customers.
The issue could be much bigger than that however: the fines only relate to direct sales made by CPP, covering 300,000 customers. It doesn't cover cases where banks themselves sold CPP's policies, thought to affect 4.1 million people.
Banks that worked with CPP include Barclays, HSBC, Royal Bank of Scotland, Standard Chartered and Yorkshire Bank, though it's not guaranteed that all of them will be found to have acted inappropriately. If the banks were all fined the same amount per case as CPP, the total bill could hit £200 million.