Google Ventures is not so quietly becoming one of the big kids in the venture capital game, as three investments so far this year show.

It’s not just the size of those funding rounds that are evidence of Google’s graduation to the next level. It's also the firms that the search giant is choosing to back:

• On Tuesday, Google Ventures participated for the first time with Sequoia Capital and others in a $32 million funding round for marketing software firm HubSpot. Sequoia, one of the giants of Silicon Valley's VC center on Sand Hill Road, was one of the early investors in a little search-engine company some kids out of Stanford were running called Google.
• Last month, Google Ventures teamed with Vinod Khosla, founder of Sun Microsystems, among others, to pour $42 million into Weatherbill, a company founded by former Google employees who are using advanced technology and forecasting to refine the crop-insurance business.
• Also in February, Google Ventures partnered with another of its parent company’s early backers, Sand Hill Road powerhouse Kleiner Perkins Caufield & Byers, and others to pour $38 million into Transphorm, a company dedicated to offering products that increase energy efficiency.

Founded in 2009 with a goal of investing about $100 million a year in a broad range of companies—from smart grids to more traditional software and Web-based firms—Google Ventures so far has put money into in at least 22 companies. Among them: HomeAway, LawPivot, Miso, RelayRides, and 23andMe.

Bill Maris, managing partner of Google Ventures, recently pointed out that his venture organization doesn’t just bring cash, but the technical prowess of Google to any deal it makes.

"We believe the diverse experience of our team, coupled with the skills and resources of Google infrastructure and 23,000 employees worldwide, provide a significant advantage to our portfolio companies and are a unique offering in the venture industry," Google Ventures says on its website.

But the recent deals and the firms it's partnering with are also a sign that, as a venture capital firm in its own right, Google Ventures is becoming a force commensurate with its parent company's strength. Not only does it draw on relationships with companies like Sequoia and Kleiner Perkins with deep Sand Hill roots and a history with Google dating back nearly to its founding, it also draws on the creativity of entrepreneurs who were once Google employees.

And going forward, it could even tap further into that strength, as it did with Weatherbill and the former Googlers who founded it. At the time, Maris said, "It feels a little like we're getting the old team back together."

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