TPG’s middle-market private equity subsidiary, TPG Growth, has closed its fourth fund with $3.7 billion in investor commitments.

The new fund pushes San Francisco-based TPG Growth’s total assets under management to more than $13 billion, including a $2.1 billion “social impact” fund that closed earlier in 2017. TPG reports that the newest fund, called TPG Growth IV, was raised in four months. The firm’s social impact fund, called the Rise Fund, has made seven investments so far.

TPG, the private equity behemoth with more than $73 billion under management, formed TPG Growth in 2007 to specialize in growth equity and middle-market buyout investments. The firm has invested in companies in the U.S., Europe, Africa and Asia, in media, technology, and industrial sectors. Its investments have included Airbnb, Beautycounter, C3 IoT, e.l.f. Cosmetics, ipsy, Papa John’s Pizza, Philz Coffee, Schiff Nutrition, Spotify, SuccessFactors, SurveyMonkey, and Uber.

On the investment front, TPG Growth has been busy in recent months. Earlier in 2017, TPG Growth reported it had formed a new company, called Xponential Fitness, to encompass StretchLab, Club Pilates and CycleBar—all fitness boutique businesses it acquired in 2017. The firm announced its acquisition of a majority stake in farm-to-fresh restaurant chain Mendocino Farms, a restaurant chain in California, from L Catterton, a Greenwich, Connecticut, PE firm.

In October, it announced it was joining family offices and investor Data Collective to finance Gro Intelligence Inc., a provider of agricultural data analytics. In September, TPG Growth announced a joint investment with QRG Enterprises Limited to take a minority stake in Campus Activewear, a sports and footwear brand. In May, the firm reported that would buy a majority stake in Medical Solutions LLC, provider of healthcare staffing services and nursing education, from PE firm Beecken Petty O’Keefe & Co. (BPOC).