Customer relationship management giant Salesforce (CRM) - Get Report is telling its retail clients that they can no longer use its software if they continue to sell certain kinds of firearms, according to The Washington Post.

Salesforce is the leading provider of software that companies use to manage their customers and communicate with them. The new policy is the latest example of large technology firms attempting to influence corporate and social behavior through their spending or by limiting access to their platforms and technologies.

Salesforce's ban is covered under its acceptable use policy that states that customers may not use a Salesforce service to "transact online sales of any of the following firearms and/or related accessories to private citizens" and proceeds to list various automatic and semiautomatic weapons, accessories and parts.

A Salesforce spokesperson told The Washington Post that the ban affects only "a small number of existing customers when their current contracts expire" and would also apply to new customers.

The Post cited retailer Camping World as a big customer that Salesforce has been pressuring to stop selling military-style rifles. The newspaper said one analyst estimated that Camping World spends more than $1 million a year on Salesforce's e-commerce software. Salesforce generated over $13 billion in revenue in its latest fiscal year ending in January. 

Salesforce did not immediately respond to a request for comment for this story.

Shares of Salesforce were down 1.6% to $153.16 on Friday and are up roughly 12% this year. The company reports its latest quarterly earnings after the close on Tuesday, June 4.

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