Google spent $4.2 billion on mergers and acquisitions during the first half of this year, with a number of Boston area firms snapped up by the company over that time period.

But what happens to all those companies after they’re absorbed by the Internet giant? Google actually has a total of 115 employees whose job it is to make sure everything goes smoothly after a company has been acquired, according to David Crandall, manager of operations for the company.

Of those 115 employees, almost half — or 56 total — are located in Google’s expanded Cambridge office, Crandall told me. Many others are located in Google’s office in Thornton, Colorado, but clearly Cambridge is playing a significant role in the company’s acquisition surge.

As Bloomberg noted, the company spent $3.2 billion for thermostat company Nest Labs Inc. this past February and an additional $1 billion on other purchases in the first six months of 2014.

The latest local company to be acquired by Google is Zync Inc., a Boston-based visual effects startup. In May, it acquired cloud monitoring service StackDriver and then earlier this month, it bought moviemaking mobile app Directr. One of its more significant transactions in the Boston area in recent years was travel search company ITA Software, which Google acquired for $700 million in 2011.