poison pill

In business, a tactic to avoid hostile takeover by making the target company unattractive. For example, a company may give a certain class of shareholders the right to have their shares redeemed at a very good price in the event of the company being taken over, thus involving the potential predator in considerable extra cost. A company may also sell a key asset, often to a friendly company, or issue employment contracts to staff with long notice periods, making it expensive to restructure.