It’s already been a hot summer for Google Ventures.

Google's venture capital investment arm recently made waves across the Atlantic when it announced the launch of a $100 million startup fund in Europe. In early June, the corporate VC firm and five other institutions invested a total of $1.2 billion in Uber. The funding round elevated the valuation of the shared-car company to an estimated $18.2 billion, according to The Wall Street Journal.

But before the firm’s recent power move in Europe and investment in Uber, it was already dominating corporate VC activity. According to CB Insights, Google Ventures best exemplifies the corporate VC industry’s shift from late-stage plays to early-stage investments. Since the first quarter of 2011, it has been the most active early-stage corporate VC, investing in more than 150 companies at the early-stage (followed by Intel Capital at 60 and Qualcomm Ventures at slightly more than 45).

Related: Who Is the Right Investor for You? That Depends on Where You Are Now.

For a more recent snapshot, here is a top 25 ranking of corporate VCs in the U.S. since the start of 2013 to May 30, 2014, based on data from PitchBook. The rise of corporate VCs in the early-stage means that, in addition to tracking traditional venture firms (ranked and listed in our VC 100) and angel investors, startups must keep a closer eye on the most active corporate VCs for funding opportunities.

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25 most active corporate VCs - money
Note: This PitchBook list displays top corporate VCs ranked by the capital invested since the start of 2013 to May 30, 2014. It ranks firms by the total invested in deals as a whole, rather than just the portion supplied by the individual corporate VC firms.

Related: Google Ventures Launches $100 Million Startup Fund in Europe