Payment processors have agreed to accept an International Organization for Standardization (ISO)-approved dealer code to identify gun purchases, Reuters reported.

The ISO on Friday approved the creation of a trade code for arms dealers, bowing to pressure from activists who see it as a measure to prosecute suspicious arms purchases, according to a separate Reuters report, citing a spokesman for the Geneva-based nonprofit.

Previously, gun shop sales were categorized as general merchandise.

Visa, Inc. v reported on Saturday that it will adopt the new “merchant category code” for US arms dealers.

“Following ISO’s decision to introduce a new code for merchant categories, Visa will proceed with the next steps while ensuring we protect all legitimate commerce on the Visa network in accordance with our longstanding rules,” the global payments processor reportedly said in a statement.

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Mastercard, Inc. MA also said it would focus on how the new code would be implemented by merchants and banks, Reuters said. American Express AXPanother peer reportedly said that when ISO develops new code, it would work with third-party processors and partners on implementation.

However, the code may not be a foolproof method of tracking because it identifies the place of purchase rather than what was purchased, the reports said.

Congressmen, leading pension funds and activists were among those calling for the implementation of such a measure to prosecute suspicious arms purchases, particularly after several incidents of mass shootings who have claimed innocent lives.

Photo: Courtesy of Michael Sächang on flickr