中文摘要
本文考察了八家主要科技公司进行的1200起初创企业收购前后的创新表现。通过将专利和员工数据与这些交易相匹配，我们记录了四项主要发现。第一，大多数被收购的初创企业不持有专利，但持有专利的企业往往在收购方已有布局、且随后还出现进一步收购活动的技术领域经营。第二，创新通常在收购前上升，收购后仅在随后还有进一步收购的领域持续，并在收购活动结束后回落。我们提出一个简化模型，其中，对商业可行性的信念同时驱动初创企业进入和收购行为，用以解释这些模式如何由选择机制而非交易本身的效应产生。第三，收购后，被收购专利获得的引用次数在统计上显著多于可比专利；这些引用不仅来自收购方，也来自雇佣了目标企业员工的企业。第四，尽管31%的员工和23%的发明人在收购后一年内离职，留任发明人此后的专利产出却要多得多，而留任者与离职者此前的生产率相当。总体而言，我们很少发现数字行业在位企业的收购抑制创新的证据，尽管连续收购与专利集中度不断上升相伴而行。
Abstract
This paper examines innovation outcomes before and after 1,200 startup acquisitions by eight major technology firms. Linking patent and workforce data to these deals, we document four main findings. First, most acquired startups hold no patents, but those with patents tend to operate in technology areas where the acquirer already has a presence and that see further acquisition activity. Second, innovation typically rises before an acquisition, continues afterward only where further acquisitions follow, and falls back once acquisition activity ends. We propose a stylized model in which beliefs about commercial viability drive both startup entry and acquisitions to explain how these patterns arise through selection rather than effects of the deals. Third, acquired patents receive significantly more citations after the acquisition than comparable patents, not only from the acquirer but also from firms that hire the targets’ employees. Fourth, although 31% of employees and 23% of inventors depart within a year, inventors who stay go on to patent substantially more, while stayers and leavers were equally productive beforehand. In the aggregate, we find little evidence that acquisitions by digital incumbents suppress innovation, even though serial acquisitions go hand in hand with growing patent consolidation.