Google forced Forbes magazine to remove a story documenting the tech giant’s manipulation of search results to promote Google Plus, its social media network, according to a former writer for the magazine.

Kashmir Hill, a longtime technology reporter for Forbes and current contributor to Gizmodo, went public with the revelation last Thursday in a post titled, “Yes, Google Uses Its Power to Quash Ideas It Doesn’t Like—I Know Because It Happened to Me”

In 2011, Hill participated in a meeting between Google salespeople and Forbes employees, in which representatives of the search giant sought to encourage Forbes to integrate its web site with Google Plus, Google’s failed competitor to Facebook.

The salespeople told her that adding a “share” button for Google Plus would boost their domain’s results in search rankings. Hill wrote,

“This sounded like a news story to me. Google’s dominance in search and news gives it tremendous power over publishers. By tying search results to the use of Plus, Google was using that muscle to force people to promote its social network.”

“I asked the Google people if I understood correctly: If a publisher didn’t put a +1 button on the page, its search results would suffer? The answer was yes.”

Hill then asked Google’s press office, explicitly identifying herself as a reporter, to confirm what she had heard in the sales meeting.

“They didn’t deny what their sales people told me: If you don’t feature the +1 button, your stories will be harder to find with Google,” she wrote.

Google responded to the publication of the story by demanding that Hill withdraw it, saying that the sales meeting was covered under a non-disclosure agreement. This was despite the fact, Hill said, that

“I had signed no such agreement, hadn’t been told the meeting was confidential, and had identified myself as a journalist.”

Google officials demanded that the article be removed, implying that Google might demote Forbes in search results if the magazine did not do what it wanted.

“The implication was that it might have consequences for Forbes, a troubling possibility given how much traffic came through Google searches and Google News,” Hill wrote.

Hill eventually agreed under pressure from Forbes to remove the article. Even more surprisingly, all cached versions of the article were almost immediately removed from Google’s servers, a phenomenon that other technology writers commented on at the time, with some implying that Google deliberately deleted the cached versions.