Airbnb just confirmed that it secretly raised $200 million from Peter Thiel's Founders Fund and others last year. But locals are more concerned about who gets a share of the "sharing economy." TF Cornerstone, the Manhattan-based real estate developer and management company with some impressive luxury listings in its portfolio, emailed tenants this morning to stop using Airbnb because it violates their lease and creates a "negative vibe."

In a memo regarding "illegal subletting," Cornerstone wrote:

It has come to our attention that some residents have attempted to list their apartments as short-term rentals on various websites. Please be advised that this behavior creates an overall security risk and a transient environment in the building. Many of our residents have complained about the security of random guests coming in and out of the building. Please refrain from using sites like airbnb, craigslist or roomorama as this practice creates a negative vibe in the building.

Please see the below information to help understand why renting out your apartment on a short term basis violates the lease.

Airbnb has chosen New York as a "model city" to fight regulatory hurdles. And TF Cornerstone's notification comes in the midst of well-orchestrated lobbying efforts to present Airbnb as the little guy trampled by outdated laws and incumbent interests. Nevermind that it has raised $320 million and it poised to make a killing as a middle man.

After Attorney General Eric Schneiderman subpoenaed user data on 15,000 Airbnb hosts in New York, "broke creatives" got spooked off trying make money on the side through the site. Now Cornerstone's memo might have the same chilling effect on the higher end of the market.

Meanwhile, Airbnb is still trying to win hearts and minds. If you caught the spate of headlines last week about how the company is a "huge boost" to New York City's economy—that data comes courtesy of a study by HR&A commissioned by Airbnb.

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