Glossary term

Anti-Takeover Measures

Anti-takeover measures are corporate defenses designed to make an unwanted takeover harder, more expensive, or less likely to succeed.

Updated

May 16, 2026

Read time

2 min read

What Are Anti-Takeover Measures?

Anti-takeover measures are corporate defenses designed to make an unwanted takeover harder, more expensive, or less likely to succeed. They can appear in a company's charter, bylaws, shareholder rights plan, state law protections, or board-approved defensive actions.

These measures are controversial because they can protect long-term strategy from opportunistic bids, but they can also entrench management and limit shareholder choice.

Key Takeaways

  • Anti-takeover measures are defenses against unwanted acquisitions.
  • Examples can include poison pills, staggered boards, supermajority voting rules, and limits on shareholder action.
  • They may protect a company from coercive bids or short-term pressure.
  • They may also reduce takeover premiums or weaken shareholder influence.
  • Investors should read a company's governance documents and proxy disclosures to understand these protections.

Common Anti-Takeover Measures

Measure

Basic purpose

Poison pill

Makes it costly for an acquirer to cross an ownership threshold

Staggered board

Prevents all directors from being replaced at once

Supermajority vote

Requires a higher approval threshold for certain actions

Greenmail response

Repurchase or restriction related to hostile blockholders

Why Companies Use Them

Boards may argue that anti-takeover measures give them time to evaluate bids, negotiate better terms, protect employees or strategy, and prevent coercive tactics. A defense can shift negotiating leverage back toward the board.

Shareholders may see the same defense differently. If a measure blocks a premium offer or makes management harder to replace, it can reduce accountability.

Anti-Takeover Measures and Tender Offers

Takeover defenses often matter when a bidder makes or threatens a tender offer. The defense may affect timing, voting power, dilution, or whether the bidder must negotiate directly with the board.

The Bottom Line

Anti-takeover measures are tools that make unwanted acquisitions harder. They can protect bargaining power, but they can also protect insiders, so investors should evaluate them through both governance and valuation lenses.

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