CBS's 'Black Rock' Building Is Said to Be for Sale

Viacom, which acquired CBS this year, plans to sell Black Rock, the elegant granite-clad skyscraper built to symbolize the broadcasting company's view of itself as ''the Tiffany network,'' according to officials involved in the discussions.

The building could be placed on the market as early as next month, the officials said.

The 38-story tower, at 51 West 52nd Street in Midtown, could fetch up to $370 million, according to real estate industry estimates. Viacom executives said that they were in the early stages of discussions with a real estate brokerage firm and that any potential sale would not involve moving many -- if any -- CBS employees. But they said those plans could change. If the building was sold with CBS continuing to occupy about half of it, the sale price would very likely be significantly reduced.

The officials from Viacom and CBS, who spoke on the condition of anonymity, said that given the hot real estate market in that area of Midtown, near Rockefeller Center, selling Black Rock would be more profitable than continuing to lease it to other tenants.

The 36-year-old building was placed on the market last year, but was taken off because the bids, which were about $300 million, were too low. But real estate industry officials say the company could get significantly more for the building now, especially if it moves many CBS employees into other Viacom buildings.

''This is a market with no vacancies, and they are one of the only significant blocks of space in Midtown Manhattan,'' said Darcy Stacom, the executive director for financial services at Cushman & Wakefield, a commercial real estate brokerage firm in Manhattan. ''Clearly, the first time CBS went to market they were offering a fully leased building. If they are now going to offer an entire block of space, it will be an attractive investment opportunity.''

If the building is sold without CBS as a tenant, Ms. Stacom estimates, it could garner as much as $425 per square foot, or about $369 million.