"They just felt that the timing was right," McCallum says of offering Fort Point Place in South Boston up for sale. The two office buildings, which total 150,000 sf, were purchased last year along with two adjacent properties that Beacon is now converting to condominiums. It has hired CB Richard Ellis/Whittier Partners to broker that deal.

The Athenaeum portfolio was purchased in May 1998 for $195 million, with Beacon earlier this summer selling one of the 11 buildings contained in that package. The 215 First St. office building traded for $68 million to Capital Properties of New York, or approximately $226 per sf. As with Technology Square, McCallum maintains that Beacon has not actively marketed the Athenaeum portfolio, but instead was approached by interested investors.

As for Technology Square, Boston Properties enior vice president David Barrett declined comment on his firm's supposed interest, saying that, "we have nothing to discuss or talk about.""People are pursuing opportunities wherever they can find them, and Cambridge is certainly a very strong market right now," says Barrett. "If we have any news about anything we are doing … we will let you know."

Despite that, one broker told GlobeSt.com that a deal is in the works with Boston Properties, a major Boston REIT that initially helped establish East Cambridge as an office destination during the early 1980s. According to the broker, "it's fairly well-known by insiders that Boston Properties is trying to buy" Technology Square.

Determining a price for the complex could be the next challenge, but one investment specialist notes that modern class A office space in Cambridge has fetched more than $300 per sf in several instances. Even at the more conservative $200 per sf mark, the purchase price would reach $328 million. Beacon has already refurbished much of the 551,000 sf of existing space, while its newest building at 300 Technology Square is said to be achieving rents above $70 per sf. The investment broker, who is familiar with the property, predicted Technology Square would "easily" exceed the $200 per sf price.

Beacon paid $123 million for Technology Square and the adjacent Draper Lab building in May 1998. It sold the 440,000-sf lab property to Draper earlier this year for $72.5 million.