Photo/Illutration The headquarters of the Japan Fair Trade Commission in Tokyo’s Chiyoda Ward. The FTC is currently investigating if Visa Worldwide Japan Co. infringed on the Anti-Monopoly Law. (Asahi Shimbun file photo)

The Japan Fair Trade Commission started an onsite inspection on July 17 at Visa Worldwide Japan Co. on suspicion of violating the Anti-Monopoly Law. 

The world's largest international credit card network is accused of demanding that credit card companies that use Visa's payment system also adopt its credit authorization system.

"If you use other companies, we will raise payment system fees,” was the threat, sources said.

Sources also believe the U.S. headquarters is involved.

"Dealing on restrictive terms" is the specific part of the Anti-Monopoly Law that has Visa under fire, as it prohibits "trade on terms that unjustly restrict business activities of transaction partners," according to the FTC's English website.

If credit card companies were to follow the alleged demand, sources said, these companies' costs would increase, and retailers and consumers would end up covering part of the costs.

Visa does not issue credit cards on its own but provides its brand's payment system to credit card companies. Payment authorization can be handled by several other entities.

The FTC will require related documents not only from Visa Japan but also from its U.S. headquarters.