"The $1.3 billion spent on acquisitions has clearly not delivered value to shareholders," Starboard said in a pointed letter to Yahoo's board. "Not only do we believe that many of the acquired companies were, and still are, losing a considerable amount of money, but we also believe that these acquisitions, on a combined basis, have failed to deliver material revenue growth," the firm added.
With a few high profile exceptions like WhatsApp, the majority of acqui-hire firms do not boast wide user bases or eye-popping valuations. In some cases, the goals of the startup may have nothing to do with the core business of the company acquiring it.
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That, however, hasn't stopped some of tech's biggest names for which buying season never seems to wane. Yahoo and Facebook snapped up at least 6 different small fish in 2014 alone, which dwarfed by the 29 swallowed whole by Google.
Industry watchers say critics like Starboard better get used to the trend, because it's not likely to go away as competition for talent tougher.
"The normal recruiting marketplace is fighting over the most skilled workers, so there is other no easy channel left to recruit talent," said John Sullivan, a management professor at San Francisco State University and former Chief Talent Officer at Agilent Technologies.
Sullivan added that acqui-hiring served another purpose: Getting employees at smaller companies entry into tech behemoths that might not consider them. "There are more startups every day and their talent will often not even consider larger firms, except through the acqui-hire process."
For its part, Yahoo insists that it approaches its acqui-hire strategy with an eye on the big picture.