He was ranked the sixth richest person in the world in 2008 but a series of setbacks -- the latest being the Supreme Court setting aside a Rs 8,000 crore arbitral award that was granted in favour of a firm in his group -- reversed his fortunes.

An MBA from Wharton School, Anil Ambani, 64, the younger son of legendary business tycoon, Dhirubhai Ambani, was known for his flamboyant nature -- he married bollywood actress Tina Munim and was a Rajya Sabha MP for two years -- as much as for his unbeatable business acumen.

But over the past few years, he has had setbacks across businesses that pushed him out of the billionaire list.

The Supreme Court on Wednesday set aside a Rs 8,000 crore arbitral award granted in favour of Delhi Airport Metro Express Pvt (DAMEPL).

The award was in relation to a dispute arising out of a "concession agreement" that was entered into between DAMEPL (a subsidiary of Anil Ambani's Reliance Infrastructure) and Delhi Metro Rail Corp in 2008.

The court asked DAMEPL to refund all sums previously paid by the Delhi Metro Rail in accordance with the arbitral award.

DMRC had paid Rs 3,300 crore to the Reliance Infra arm, which now needs to be refunded.

Anil Ambani's Reliance Infrastructure Ltd in a stock exchange filing that no liability has been imposed on it by the Supreme Court order.

"Reliance Infrastructure wishes to clarify that the Order dated April 10, 2024, passed by the Supreme Court does not impose any liability on the company and the company has not received any money from DMRC/DAMEPL under the arbitral award," it said.

While DAMEPL is a subsidiary of Reliance Infrastructure, it is a separate entity and the liability falls on it.

After Dhirubhai suffered a stroke in 1986, Anil took on day-to-day management of Reliance's financial relationships under his father's oversight.

He and his elder brother, Mukesh, assumed joint leadership of the Reliance companies after their father's death in 2002.

But soon after they feuded over control, leading to split -- Mukesh got control of flagship oil and petrochemicals, while Anil gained control of the newer businesses such as telecommunications, power generation, and financial services through a 2005 demerger.

The two brothers, who had diverging fortunes thereafter, did not stop fueding. They fought over supply of gas from fields operated by Mukesh's company to the power plant of Anil's group.

The elder brother won the case in Supreme Court which said a family pact cannot override a government's allocation policy.

Anil borrowed money to fuel an expansion with forays into infrastructure, defence and entertainment businesses.

In 2009, the Allahabad High Court quashed land acquisition for the proposed mega gas-based power project at Dadri in Uttar Pradesh by Anil's group.

A non-compete clause between the brothers kept Mukesh out of telecom but that was scrapped in 2010.

Mukesh quickly returned, pumping in more than Rs 2.5 lakh crore over the next seven years to build a speedier 4G wireless network, which drove out competition, including Anil's Reliance Communications (RCom).

His venture into the entertainment business with a USD 1.2 billion deal with Adlabs in 2005 and DreamWorks in 2008 did not work. In 2014, his power and infrastructure companies plunged into huge debt.

Anil sold assets to quell investor concerns around the indebtedness of some of his companies. He sold companies like Big Cinema, Reliance Big Broadcasting, and Big Magic.

RCom, which ushered in a telecom revolution in the country, was sent to insolvency proceedings to repay debt.

His bets on defence manufacturing, too, failed.

In 2019, the Supreme Court had threatened Anil Ambani with prison after Reliance Communications (RCom) failed to pay Rs 550 crore to Ericsson AB's Indian Unit.

The court gave him a month to find the funds and Mukesh Ambani bailed him out at the last moment by giving the required money.

In 2019, three Chinese banks dragged Anil Ambnai to a London court over a USD 680 million loan default.

Industrial & Commercial Bank of China Ltd, China Development Bank and the Export-Import Bank of China had in 2012 agreed to loan USD 925 million to his group firm Reliance Communications on condition that he provide a personal guarantee.

RCom defaulted and the three banks sued Ambani, who said he agreed to give a non-binding "personal comfort letter" but never a guarantee tied to his personal assets. The matter is still in court.

Reliance Capital filed for bankruptcy in 2021 after defaulting on bonds worth Rs 24,000 crore.

Reliance Infrastructure Ltd, which built Mumbai's first metro line, missed a bond payment as it waited for proceeds from the sale of power transmission assets to Gautam Adani's unit to cover the amount.

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