Kick-in or trigger point
The level of share ownership by an acquiring firm that activates the poison pill antitakeover defense plan.

Kick-in-the-pants hypothesis
Attributes the increase in a takeover target's stock price to the impetus given by the bid to target management to implement a higher-valued strategy.

資料來源：J. Fred Weston, Mark L. Mitchell, and J. Harold Mulherin, “Takeovers, Restructuring, and Corporate Governance”, Forth Edition, Pearson Educational International