Based in Pasadena, CA, Alexandria secured the properties beginning in 2001 when it paid $35.6 million for 770, 784 and 790 Memorial Dr., the middle of which served as the long-time headquarters of Polaroid Corp. That property is well known thanks to an art deco design and prominent clock that serves as the centerpiece. After Polaroid was forced to sell in 1999 to the Bulfinch Cos. due to lingering financial difficulties, the 3.8-acre complex overlooking the Charles River was purchased by Alexandria during construction of 770 and 790 Memorial Dr., a pair of laboratory structures totaling 100,000 sf.

Alexandria subsequently acquired 161-171 and 170-176 Sidney St. as a package in late 2005 for $4.8 million; paid $72.7 million for the 128,000-sf 300 Third St. in March 2006; and bought three properties on Brookline and Erie streets for $11.1 million a year ago this month, headlined by 99 Erie St. The total price paid by Alexandria for the properties involved in the MIT deal was $124.2 million.

Calls to Alexandria were not returned by GlobeSt.com's press deadline, while efforts to garner insight from MIT about its motivations were also unsuccessful. One industry observer says the arrangement is unique in terms of the deal's length and the apparent likelihood that Alexandria will play an active role leasing the buildings to third parties.