MUMBAI, March 15 (Reuters) - Some of India's biggest companies were among the country's top political funders over the last five years under a now-scrapped opaque political funding system, official data showed.

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

Following are the top 10 buyers of the bonds, according to official data:

1. Future Gaming and Hotel Services - the lottery and gaming firm topped the list with a total donation of 13.68 billion Indian rupees ($165 million) between April 2019 and January 2024.

Based in the southern state of Tamil Nadu, the company, previously known as Martin Lottery Agencies, also has interests in real estate and construction businesses with annual revenues of over $2 billion, its website says. The company is headed by Santiago Martin, also known as the "Lottery King" of India. According to the firm's website, Martin has been India's highest income tax payer for several years.

2. Megha Engineering and Infrastructures Ltd - the Hyderabad-based engineering and construction firm came second by buying bonds worth 9.66 billion rupees. Its subsidiary, Western UP Power Transmission, also bought electoral bonds worth 2.2 billion rupees.

Specialists in building all-weather tunnels and high-speed rail infrastructure, the firm counts the Zojila Road tunnel in the Himalayas and other top government projects among its landmark ventures.

3. Qwik Supply Chain Private Ltd - The Mumbai-based company specialises in providing logistics, warehousing and manpower support services and bought bonds worth 4.1 billion rupees.

4. Vedanta Ltd - The metals and mining conglomerate, led by billionaire Anil Agarwal, donated 4.01 billion rupees. Agarwal tried unsuccessfully to take Vedanta Ltd, a unit of UK-based Vedanta Resources, private in 2020 and his latest plan was to split the company into six.

5. Haldia Energy Ltd - A unit of the RP-Sanjiv Goenka Group , Haldia Energy runs a thermal power plant in the port city of Haldia in West Bengal state and bought electoral bonds worth 3.77 billion rupees.

Goenka also owns the Lucknow franchise in the popular Indian Premier League cricket tournament and the Kolkata-based Mohun Bagan football club in the Indian Super League.

6. Essel Mining and Industries Ltd - the company, which donated 2.25 billion rupees, is one of India's largest private coal miners and is part of the telecom-to-metals conglomerate Aditya Birla Group.

7. Western UP Power Transmission Co Ltd - WUPPTCL, which bought bonds worth 2.2 billion rupees, is one of India's largest power transmission projects built by Megha Engineering and Infrastructures Ltd.

8. Bharti Airtel Ltd - India's No. 2 telecom carrier by subscribers bought electoral bonds worth 1.98 billion rupees.

9. Keventer Food park Infra Ltd - The Kolkata-based firm bought bonds worth 1.95 billion rupees. The company is in the food and dairy-based beverages sector and exports pulp and agricultural products.

10. MKJ Enterprises Ltd - Another Kolkata-based firm, MKJ Enterprises deals in the steel business and bought bonds worth 1.92 billion rupees. ($1 = 82.8638 Indian rupees)

(Reporting by Sudipto Ganguly; Editing by YP Rajesh and Susan Fenton)