Carl Icahn and banks have agreed to amend loan agreements that untie the billionaire's personal loans from the trading price of Icahn Enterprises, the Wall Street Journal reported, months after short-seller Hindenburg's criticism triggered a massive fall in the shares of his investment company.

Shares of Icahn Enterprises soared 7.5% in premarket trading on Monday. They are down about 43% since the Hindenburg report came out in May.

Icahn will now provide additional collateral, which will total roughly $6 billion, including $2 billion of his own funds, and laid out a plan to repay the loans in three years, the report said on Monday, citing people familiar with the matter.

IEP did not immediately respond to a Reuters request for comment on the report.

Hindenburg had called Icahn's pledge of about 60% of his IEP stake as collateral for margin loans as risky, which could result in margin calls should the unit's prices decline.

The short-seller accused IEP of overvaluing its holdings and relying on a "ponzi-like economic structure" to pay dividends. It also said IEP units were inflated by more than 75%.

Icahn called Hindenburg's report "self-serving" and vowed to "fight back."

Following the amendment, the only thing that could now trigger a margin call is movement in the net asset value of his company’s investments, which include companies and stocks, the report said.