The Wikimedia Foundation, a nonprofit that operates Wikipedia and related projects, explained yesterday that it will establish new rules covering paid editing.

The heart of the change is that anyone who is paid to edit the site must "add your affiliation to your edit summary, user page, or talk page, to fairly disclose your perspective," according to Wikimedia's explanation of the change. The organization has also published an FAQ on paid editing.

The changes come after some high-profile commotions over paid editing. In October, Wikipedia deleted more than 250 accounts believed to be connected to a PR firm that was writing articles on the site. In January, the Wikimedia Foundation fired an employee who was accused of taking paid editing gigs.

Among the world's most heavily trafficked websites, Wikipedia ranks sixth, according to Alexa. It's the only top website that's owned by a non-profit.

Some Wikipedia editors are paid indirectly, because they work for a gallery, library, archive, or museum that allows them to write about their area of expertise as part of their job. The new directive is not aimed at such workers, who only have to make specific disclosures if they write about the actual institution they work for.

Similarly, a professor working at a particular university would only have to make a disclosure if she was paid directly by the university to write about that university. If the professor "is only encouraged by their university to contribute generally without more specific instruction, that professor does not need to disclose their affiliation with the university," explains the new FAQ.

Anyone editing for a public relations firm will have to disclose both the firm and the client they're working for, according to the new rules.

For unpaid volunteer editors, nothing will change. "Please keep editing!" urges the Wikimedia blog post by Geoff Brigham, the organization's top lawyer. "You're part of an amazing community of volunteers contributing to an unprecedented resource of free information available to the whole world."