Icahn Enterprises' Stock Plummets as Rivals Weigh In and Holdings Drop.

The market value and stock for Icahn Enterprises (IEP) has plummeted since short-selling firm Hindenburg Research claimed that the company has been using inflated asset valuations and "ponzi-like economic structures." IEP's market cap was cut by more than half this month, and the stock has fallen almost 63% since the start of May. Billionaire Carl Icahn has pushed back against Hindenburg's report, calling it "self-serving," while longtime rival Bill Ackman has doubled down on the allegations and questioned why Icahn has not disclosed the terms of his market loans.