Killer bees are companies or individuals—such as investment bankers, accountants, attorneys, and tax specialists—that help target firms avoid being taken over by an unwanted suitor. Their job is to devise and implement anti-takeover defence strategies, which generally consist of making the target less attractive or more difficult or costly to acquire.
When a company targets another one for acquisition, it will usually first approach its board of directors. If rebuffed, the acquirer could then return with a better bid, walk away, or seek to bypass management by initiating a tender offer directly to shareholders.
Should takeover advances turn unfriendly or hostile, killer bees may be brought on board. Their job is to come up with feasible ways to make life uncomfortable for the prospective buyer, similar to how their namesake stings its victims when provoked until they back off and go away.
Killer bees rose to prominence during the 1980s hostile takeover craze. Back then, a category of investors with deep pockets, known as raiders, began buying undervalued companies and then controversially dismembering them to bag a quick profit. Corporate America wasn't used to this type of behaviour and enlisted the help of specialists to defend against these attacks.
Killer bees would present a series of options to the target's board based on its individual circumstances and the characteristics of the company seeking to buy it. To foil a hostile takeover attempt, they generally aim to make the prey either too expensive to acquire or so unattractive that the predator loses interest.