Facebook Inc prohibits private firearms transactions on its online social networks

Facebook already prohibited private firearms sellers from advertising "no background check required," or offering transactions across U.S. state lines without a licensed dealer because the company said such posts indicated a willingness to evade the law.

Licensed retailers will still be able to advertise firearms on Facebook that lead to transactions outside of Facebook's service.

From reuters: 
Facebook Inc (FB.O) prohibited global users from coordinating person-to-person private sales of firearms on its online social network and its Instagram photo-sharing service on Friday, countering concerns that it was increasingly being used to circumvent background checks on gun purchases.

The move comes as the United States debates the issue of access to guns after a string of mass shootings. U.S. President Barack Obama has urged social media companies to clamp down on gun sales organized on their platforms.

It updates Facebook's regulated goods policy, introduced in March 2014, that banned people from selling marijuana, pharmaceuticals and illegal drugs.

Facebook already prohibited private firearms sellers from advertising "no background check required," or offering transactions across U.S. state lines without a licensed dealer because the company said such posts indicated a willingness to evade the law.