The Federal Deposit Insurance Corporation (FDIC) and Consumer Financial Protection Bureau (CFPB) say that Discover used "deceptive" telemarketing and sales tactics to convince Americans to pay for things like payment protection, credit score tracking and identity theft protection.

The firm, which has also been fined $14 million, gave employees telemarketing scripts that contained misleading language "likely to deceive consumers about whether they were actually purchasing a product," say the FDIC and CFPB.

Marketers downplayed key terms and spoke quickly during the part of the call in which the details on add-on products were disclosed. Not only were customers mislead on whether they had bought products, they were often left unclear on whether products cost anything and were sometimes enrolled without giving consent.

Discover will split $200 million between 3.5 million tricked customers who were charged for one or more of the products between December 2007 and August 2011. It has also promised to stop the practices and submit to an independent audit.