Many accepted generous buyouts from the companies they threatened to take over, a perfectly legal form of corporate extortion known as "greenmail."
Among the first to be labeled a "greenmailer" was none other than Carl Icahn.
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They were paid handsomely to sell their stock back to the company, at a premium, if they would just go away, promising never to return. (That was politely called a "standstill agreement.")
When all was said and done, the raiders/greenmailers/financiers enriched themselves at the expense of corporations, and their shareholders, but claimed the high ground by pointing to rising share prices of the companies they targeted. Rarely did the bemoan the immense debt they saddled the companies with, that would eventually, create a crisis in the stock market.
In the aftermath of all those the raids, and the subsequent debt defaults they triggered, that style of investing fell into disrepute, as raiders of the lost art fell on hard times, lost their influence, or went to jail for trading and profiting on inside information. And that was at the end of the "roaring '80s."
During the peak of the plundering, the raiders were often compared to the "robber barons" of the Gilded Age.
However, the "robber barons" actually built America's corporate, and physical, infrastructure while their descendants tore it apart.
Sadly, the raiders are mounting a comeback. Some of them are aging greenmailers of years gone by. Some are new, and some are legitimate "activist" investors who seek to improve the quality of the businesses they target.