The Supreme Court building is seen in New Delhi, India, Dec 11, 2023. (PHOTO / AP)

NEW DELHI - Some of India's biggest companies, including Vedanta Ltd, Bharti Airtel, RPSG Group and Essel Mining were among the country's top political funders over the last five years under a now-scrapped opaque political funding system, official data showed on Thursday.

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The information was made public by the Election Commission of India following an order on Monday from the country's top court, just days before a national election is due to be called.

The political funding mechanism introduced in 2017 allowed companies and individuals to donate unlimited amounts anonymously to political parties.

Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) was the largest beneficiary of these bonds, which were donations, garnering 55 percent of the bonds worth 120 billion rupees ($1.45 billion) donated between January 2018 and January 2024 by people and companies

The funding system, called Electoral Bonds, was challenged by opposition lawmakers and a civil society group on the grounds that it hindered the public's right to know who had given money to political parties.

The Supreme Court banned Electoral Bonds last month, calling them "unconstitutional".

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Under the system, a person or company could buy bonds from government-owned State Bank of India and donate them to a political party.

Prime Minister Narendra Modi's Bharatiya Janata Party (BJP) was the largest beneficiary of these bonds, which were donations, garnering 55 percent of the bonds worth 120 billion rupees ($1.45 billion) donated between January 2018 and January 2024 by people and companies.

The decision to scrap the funding system was seen as a setback for the BJP as well as other main political parties as it came ahead of the national election due to be held by May.

SBI told the Supreme Court on Wednesday that it had sold a total of 22,217 electoral bonds of various denominations of which 22,030 were cashed in by political parties between April 1, 2019 and Feb 15, 2024.

A list of the top 20 electoral bond buyers compiled by Reuters showed lottery and gaming firm Future Gaming and Hotel Services topping the list with a total donation of 13.68 billion rupees.

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Megha Engineering and Infrastructures, an engineering and construction firm based in the southern city of Hyderabad, came second at 9.66 billion rupees.

It was followed by logistics firm Qwik Supply Chain, natural resources giant Vedanta and Haldia Energy.

Reuters emailed the top 10 businesses on the list seeking comment but there was no immediate response from any outside business hours.