For months, Wikipedia has been battling a company called “Wiki-PR,” which purportedly sells paid editing services on the well-known online encyclopedia. In October 2013, Wikipedia announced it blocked or banned hundreds of editor accounts in response.

Now the Wikimedia Foundation (which runs Wikipedia) is escalating its game: on Tuesday it issued a cease and desist letter to Wiki-PR, demanding that the company immediately halt editing Wikipedia “unless and until [Wiki-PR has] fully complied with the terms and conditions outlined by the Wikimedia Community.”

Based on the three-page letter, which the Wikimedia Foundation published on its website Tuesday afternoon, it appears that Wikimedia attempted to solve the situation amicably prior the situation reaching this stage.

The attorney representing the Wikimedia Foundation, Patrick Gunn, wrote:

In your communications with me and the Foundation, you have stated your intent to work with the community to satisfy its conditions for lifting the ban. Yet, yesterday, you admitted that Wiki-PR has continued to actively market paid advocacy editing services despite the ban—consistent with evidence that we have discovered independently. This is deeply troubling and suggests that Wiki-PR is circumventing the ban at the same time it professes to engage with the community about complying with it.

Ars has contacted Wiki-PR for comment but did not receive an immediate reply.

Gunn concluded: "Should you fail to comply with the terms of this cease and desist letter, Wikimedia Foundation is prepared to take any necessary legal action to protect its rights."