Poison Pill
A poison pill, formally a shareholder rights plan, deters an unapproved ownership accumulation through specified rights and dilution triggers.
Compare shareholder rights plans and self-tender offers by trigger, dilution, funding, ownership effect, and shareholder choice.
Poison pills and issuer tender offers are distinct takeover-related tools. A poison pill, or shareholder rights plan, can make an unapproved ownership accumulation highly dilutive after a specified trigger. A self-tender offer uses company cash or financing to repurchase its own securities directly from holders.
The first changes the economics of crossing an ownership threshold; the second is an actual capital-allocation transaction if it settles. They should never be treated as synonyms.
| Feature | Poison pill | Self-tender offer |
|---|---|---|
| Primary mechanism | Rights issued to eligible holders can create dilution after a trigger | Company offers to buy a stated amount of its own securities |
| Immediate cash use | Usually limited before exercise or exchange | Potentially substantial when securities are purchased |
| Main takeover effect | Discourages stake accumulation without board approval | Changes shares outstanding, ownership percentages, liquidity, and leverage |
| Holder action | Usually no immediate election before a trigger | Each holder decides whether and how much to tender |
| Key terms | Trigger, beneficial ownership, exemptions, duration, redemption, exchange | Price or range, amount sought, funding, expiration, proration, withdrawal |
| Central U.S. filing evidence | Rights agreement, board disclosure, ownership reports | Schedule TO, offer to purchase, amendments, final results |
Assume a company has 100 million shares, $900 million of cash, and no net debt. An outside investor owns 12% and is considering increasing its stake.
The board could adopt a rights plan with a 15% trigger. Before a trigger, the company generally has not spent the billions that full dilution might imply. The relevant analysis is how the rights agreement defines beneficial ownership, exemptions, redemption, exchange, and expiration, and whether the threshold affects legitimate shareholder activity.
Alternatively, the company could offer to repurchase 20 million shares at $25 each. If fully subscribed and completed, the self-tender would use $500 million before fees and leave 80 million shares outstanding. The outside investor’s percentage would rise if it did not tender while other holders did, subject to the actual participation and proration.
The self-tender therefore consumes liquidity and can increase the investor’s percentage even without another purchase. The rights plan does not create that same immediate balance-sheet effect. A board must model the actual tool rather than discuss both as generic defenses.
The trigger is not the bidder’s maximum legally permitted ownership in every context. It is a contractual threshold under the rights plan, subject to the plan’s definitions and applicable law.
Investor.gov’s tender-offer guide distinguishes issuer tenders from third-party offers and explains holder choice and minimum conditions. The SEC transaction and filer reference identifies Rule 13e-4 and Schedule TO for issuer tender offers.
These pages are educational and do not provide takeover-defense, securities, legal, tax, accounting, valuation, voting, or investment advice.
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A poison pill, formally a shareholder rights plan, deters an unapproved ownership accumulation through specified rights and dilution triggers.
A self-tender offer is a structured offer by a company to repurchase its own securities directly from holders.