Three of Japan's top credit card companies -- Credit Saison Co., Orient Corp. and UC Card Co. -- have agreed to integrate their core operations systems by 2010, officials of the card companies said Friday.

The three companies, which have about 45 million cardholders combined and an estimated 20 percent share of card settlements, will spend about 30 billion yen to jointly develop a new system for storing basic data, such as records of purchases and settlements.