The 690 Canton St. leases were for McDonald's at 12,695 sf, Merck, the pharmaceutical giant, at 10,856 sf and VerifEyes, a startup mail-server software provider at 2,496 sf. The transactions bring the three-story 164,695-sf building to full occupancy.

The SAS Institute, relocating from Wakefield, leased the top two floors for five years at the Ferncroft Corporate Center, which was acquired by Berwind less than 30 days ago for $19 million. This brings its occupancy rate to 82%.Built in 1999, Ferncroft is an eight-story 226,088-sf building.

The leasing success is consistent with Berwind's overall strategy of buying office properties, leasing them up, and flipping them in a relatively short time, generally five years, according to Albert Corr, vice-president at Berwind.

"We're outperforming the market with our properties," he tells GlobeSt.com. When we bought (Ferncroft Center), the vacancy rate was similar to others in the market, and we've been able to add value (in a short period of time)."

Research bears that assertion out. Berwind assets 100 Cambridge Park, the Campus at Marlborough, and 690 Canton St. were all purchased with high vacancy rates and now are 100% occupied. Other properties such as 1210-1230 Washington St. in Newton, 60 Temple Place in Boston and 181-187 Ballardvale are at 75 to 81% occupancy rates and outperforming similar properties in their respective markets.

"Our strategy is on an asset-by-asset basis," Corr adds. "We would be classified as a value added investor/operator. We're looking to create value in the Boston market. We've been able to buy moderate- to high-vacancy properties, add value, and then release them into a volatile market. We're not going to be buying properties with 15 years bonding to one tenant."