NYT: How to hold a voting stake in a company without economic interest

The NYT reports in an article entitled Nothing Ventured, Everything Gained that a "new trading tactic that could tip proxy fights and takeover battles has emerged from the shadows of the hedge fund industry, igniting outrage among some investors and corporate governance experts.
The tactic is a complex hedging technique that allows an investor to buy a voting stake without actually holding an economic interest in the company. While Wall Street has long speculated about such a tactic, it was not until this week that the first signs of such a strategy were disclosed amid a takeover fight for King Pharmaceuticals, a generic drug maker, by its larger rival, Mylan Laboratories."