Major competition regulators, and substantial portions of the scholarly community, have rapidly adopted the view that “killer acquisitions†and “kill zones†constitute significant sources of competitive risk arising from incumbent acquisitions of emerging firms in digital markets. Based on this view, policymakers in the United States, European Union, and other jurisdictions have advocated for, and in some cases have taken, substantial changes to merger review policies that would erect significant obstacles to incumbent/startup acquisitions. A review of the relevant body of evidence finds that these widely-held views concerning incumbent/startup acquisitions rest on meager support, confined to ambiguous evidence drawn from a small portion of the total universe of acquisitions in the pharmaceutical market and theoretical models of acquisition transactions in information technology markets. Moreover, the emergent regulatory and scholarly consensus fails to take into account the rich body of evidence showing the critical function played by incumbent/startup acquisitions in supplying a monetization mechanism that induces venture-capital investment and promotes startup entry in technology markets. The prospect of an acquisition transaction in the case of technical and commercial success generally promotes innovation and competition by providing a transactional device that expands startups’ access to the capital inputs required to undertake R&D and the commercialization services required to convert R&D outputs into commercially viable products. At the same time, these acquisitions enable incumbents to access the specialized innovation capacities of smaller firms. Proposed changes to merger review standards would disrupt these efficient transactional mechanisms and are likely to have counterproductive effects on competitive conditions in innovation markets.