Based on the aggregated intelligence of 170,000-plus investors participating in Motley Fool CAPS, the Fool's free investing community, office REIT Boston Properties (NYSE: BXP) has received the dreaded one-star ranking.

With that in mind, let's take a closer look at Boston Properties' business and see what CAPS investors are saying about the stock right now.

Boston Properties facts

Headquarters (Founded) Boston (1970)
Market Cap $15.8 billion
Industry Office REIT
Trailing-12-Month Revenue $1.6 billion

Co-Founder/Chairman/CEO Mortimer Zuckerman

CFO Michael LaBelle

Return on Equity (Average, Past 3 Years) 3.7%
Cash/Debt $747.3 million / $7.9 billion
Dividend Yield 1.8%

Mack-Cali Realty (NYSE: CLI)

SL Green Realty (NYSE: SLG)

Vornado Realty Trust (NYSE: VNO)

Sources: Capital IQ (a division of Standard & Poor's) and Motley Fool CAPS.

On CAPS, 49% of the 327 members who have rated Boston Properties believe the stock will underperform the S&P 500 going forward. These bears include investorpoet2 and kurtdabear.

Late last month, investorpoet2 touched on Boston Properties' seemingly unsustainable valuation: "High quality REIT with a strong balance sheet, but headwinds in real estate are not over. BXP has a [funds from operations yield] of 4.28% and a dividend of 1.90%, which indicate lackluster returns for the next several years."

In fact, Boston Properties currently sports a particularly lofty price-to-cash flow of 34. That represents a premium to other office REITs like Mack-Cali (14), SL Green (20), and Vornado (26).

CAPS member kurtdabear elaborates on the Boston Properties bear case:

Office vacancies are high and rising in most of BXP's markets, with Washington, D.C. being the main exception (for obvious reasons); and dividends are running way ahead of income. Something's got to give, and I think it's going to be BXP's value, as rents and property values begin to erode from lack of demand.

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