Within banking, product control are a team responsible for the accounting and financial reporting of a trading desk. They are responsible for the monitoring of trades in the portfolios they look after, and act as a primary control function; monitoring trading activity to ensure it is within a specified limit.
In turn product controllers are responsible for ensuring traders mark their books to fair value prices.
There have been many high-profile cases of where banks have been fined for this control not working effectively, examples including the USA's financial services regulator, the Securities and Exchange Commission, fining European Investment Bank Credit Suisse over mis-marking bonds during the height of the subprime credit crisis.
Poor product control procedure were also noted in the collapse of US investment Bank Lehman Brothers.