Not content to take a stake in a company and push for management change or asset realization strategies, Carl Icahn is increasingly submitting tender offers for companies, with recent deals showing unpromising results.

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Electronic trading and the proliferation of computer-based trade execution programs has given birth to these companies and so-called dark pools, which help brokers or asset management firms move huge blocks of shares at once without tipping off the markets.

FORBES: Crank Up The Volume