Of the most highly-valued VC-backed companies, Dropbox has been far and away the most acquisitive, followed by AirBnB, Pinterest and Square.

Data analytics and software company Palantir Technologies commands a $9B valuation in the private markets but has shown little interest in making acquisitions – until now. In the last week of July, the Palo Alto, Calif.-based firm announced the acquisitions of two seed VC-backed startups – social polling startup Poptip and mobile app development startup Propeller.

So we wondered how Palantir’s recent acquisition uptick compared against the acquisition activity of other highly-valued private startups. And based on CB Insights data, it’s apparent that a number of unicorns-in-waiting are becoming increasingly acquisitive.

First, which startup companies are we evaluating?

The chart below highlights the 10 most highly-valued U.S.-based venture-backed companies based on valuations fetched in the private markets. This list is led by Uber, which recently raised funding at an $18.2B valuation. While Snapchat is only rumored to be raising at a $10B valuation, the company was also included for the purposes of this analysis.

mosthighlyvaluedIn terms of acquisition activity, Dropbox has been far and away the most acquisitive disclosing 18 different acquisitions to-date mostly around mobile software. The cloud storage firm has been on a summer M&A binge. Most recently Dropbox acquired eCommerce analytics firm Predictive Edge Technologies, which appears to be an acqui-hire. In June, Dropbox acquired three other startups including Parastructure, Droptalk and MobileSpan, respectively.

After Dropbox, AirBnB, Pinterest and Square have been most acquisitive with each having disclosed six, five and five acquisitions respectively. Among the most expensive acquisitions by the potential unicorns was Jawbone’s acquisition of BodyMedia, a wearable tech company, as well as Mailbox which was acquired by Dropbox.  Both deals were rumored to be valued at around $100 million. On an unrelated note, Mailbox has performed well against a crop of VC-backed email apps that have sprouted up suggesting that Dropbox may have made a smart move with this deal.

Notably, Uber has not disclosed any acquisitions despite intense competition in the ride-sharing market and the company’s own moves into adjacent areas. While there has been a wave of M&A in flash storage, Pure Storage also appears to have yet to find any M&A targets worth purchasing.

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While some of the deals as mentioned were for notable sums, most appear to be acqui-hires. As more tech orphans emerge, this trend may accelerate especially given some of the mega-financing rounds being done by these companies.

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