Instrumentation Laboratory is a tenant at the adjacent 101 and 113 Hartwell Ave., the latter of which was owned by Gateside Corp. through affiliate Gateside Lexington LLC. The Rye, NY-based firm had held a stake in 113 Hartwell Ave. for nearly 20 years. Efforts to contact company officials by press deadline were unsuccessful, keeping unanswered the question of whether the sale was prompted by Instrumentation's pending departure, a notion advanced by one observer familiar with the property. "It's going to take some work" to reposition the asset, says the broker, maintaining that Gateside opted to hand that chore over to another investor.

Gateside also owns 5 Chrysler Rd. in Natick. It is unclear whether the firm has any other Massachusetts holdings. Gateside has ventured into various asset classes over the years throughout the northeast, including industrial, multifamily and office.

Neelon is focused on the Route 128 Central strip that includes its flagship asset in Waltham, Overlook Center, where the firm and Normandy Real Estate Partners are constructing one of suburban Boston's newest office buildings, the six-story, 105,000-sf Overlook Center. Based in Waltham, located just a few miles south of Lexington, Neelon has been on a bit of a buying spree lately, having also this year acquired 2 Liberty Sq. in downtown Boston in partnership with AEW. The $23-million sale of that 11-story, 60,000 sf office building was first reported by GlobeSt.com on July 26th.