Decades in the past, Carl Icahn gained a formative perception from studying the American novelist Theodore Dreiser. The billionaire investor was absorbed by two of Dreiser’s novels, The Financier and The Titan, which chronicle the rise of industrialist Frank Cowperwood.

In a decisive monetary stand-off, Cowperwood’s adversaries plot to have a financial institution name in his giant private money owed. But unbeknown to them, Cowperwood holds a big reserve of belongings that “could be drawn on and hypothecated”. Were it to be deployed, Dreiser writes, “these men should see at last how powerful he was and how secure”. Cowperwood prevails and Icahn says he learnt an important lesson: all the time have a “war chest” of money.

The 87-year-old is famed for his many years spent orchestrating shareholder fights with corporations together with Texaco, Trans World Airlines, Apple and McDonald’s. These battles have reshaped US monetary markets by altering how firms are run, steering their administration in the direction of the pursuits of huge stockholders like Icahn.

For almost half a century, the mere point out of his identify has struck terror within the hearts of company chieftains and moved markets. But a lot of Icahn’s energy emanated from an obscure, thinly traded public automobile referred to as Icahn Enterprises that has largely gone unexamined.

This month, Icahn was besieged by a sceptic named Nathan Anderson who, in a report revealed by his agency Hindenburg Research, uncovered heavy money owed the investor had taken towards his Icahn Enterprises shares. The revelation has uncovered a stunning vulnerability in one of many world’s wealthiest financiers. Icahn has vowed to “fight back”, however his plans to safe his empire stay principally a thriller.

In latest years, Icahn made ever-larger bets towards a fast-rising market to guard his investments from a future crash. Instead of constructing an emergency reserve, the trades have led to just about $9bn in losses. When confronted with these losses final week, a circumspect Icahn admitted: “Maybe I made the mistake of not adhering to my own advice in recent years.”

The predicament has shocked many senior figures on Wall Street. “It’s one of those moments in a crisis where you go, ‘Holy shit, everything I thought about somebody was wrong,’” stated the top of a big monetary agency.

Bill Ackman, a billionaire investor whom Icahn tussled with in a legendary battle over the destiny of a multilevel advertising firm, provided probably the most brutal evaluation. “Icahn’s favourite Wall Street saying [is]: ‘If you want a friend, get a dog,’” Ackman wrote on Twitter. “Over his storied career, Icahn has made many enemies. I don’t know that he has any real friends. He could use one here.”

Born to schoolteachers in 1936, Icahn was raised within the working-class New York neighbourhood of Far Rockaway, Queens. After graduating from an area public highschool, he earned a philosophy diploma from Princeton University and supported himself utilizing poker winnings.

He briefly enrolled in medical faculty, however dropped out and joined the military earlier than settling down as a stockbroker. In the late Sixties, a rich uncle bankrolled Icahn’s buy of a seat on the New York Stock Exchange, the place he grew to become a specialist in “risk arbitrage”, bets on anticipated company mergers.

Icahn entered public consciousness within the Nineteen Eighties when he received management of Trans World Airlines utilizing financing from junk bond king Michael Milken. He ruthlessly bought TWA belongings for money, and battled unions, incomes a fame as a “corporate raider”. The episode helped encourage the character Gordon Gekko within the movie Wall Street.

In latest years, Icahn, who divorced his first spouse and married his assistant, Gail, has moved his agency from a skyscraper overlooking Manhattan’s Central Park to Miami. He has additionally labored extra carefully along with his grownup youngsters, Brett and Michelle.

Brett helped establish profitable bets on Apple and Netflix and has been named his father’s eventual successor. Michelle’s work on the Humane Society impressed Icahn to run an unsuccessful marketing campaign towards McDonald’s over its therapy of livestock.

The assault on Icahn comes as he continues to battle corporations he deems poorly managed. On Thursday, he achieved a attract a warfare towards Illumina, an organization that makes machines to sequence the human genome. Icahn accused Illumina’s administration of hanging reckless acquisitions and requested its stockholders to present his nominees three board seats. He was capable of oust Illumina’s chair, however did not win the 2 different seats, which might have helped him dethrone its chief govt. The consequence underscores his enduring affect. But he’s in uncharted territory.

This week, Icahn Enterprises plunged by greater than 30 per cent, including to a drubbing that has reduce the corporate’s worth by greater than half. It has value Icahn billions and made the specter of a “margin call” from his lenders extra speedy.

Whether he can prevail could properly come right down to the lesson he says he learnt from Dreiser’s Cowperwood many years in the past. Icahn instructed the Financial Times final week he had billions sitting outdoors his public automobile. If so, the “war chest” would give him yet one more hand to play.

antoine.gara@ft.com

Additional reporting by James Fontanella-Khan