Shares of Tata Power tumbled 4% on Thursday after the Singapore International Commercial Court dismissed the company’s challenge to a $490 million arbitration award over a dispute with investor Kleros Capital Partners.

Tata Power shares sharply dropped to Rs 349.50 apiece on Thursday morning, the lowest level seen by the stock since early February this year. The stock is on track to record the sharpest single-day fall in nearly 17 months.

What is the case all about?

The case dates back to 2013 when investor Kleros Capital Partners approached Tata Power with a proposal to jointly bid for a Russian coal deposit. Tata Power entered into a non-disclosure agreement with Kleros for four years from September 2013.

However, the relationship between the two parties began to sour in 2015 as disagreements over who would lead the bid and the ownership structure began to emerge before the relationship subsequently ended the next year, Bloomberg cited a court document as saying.

While Kleros did not bid for the mine, Tata Power submitted a bid through a Russian subsidiary and won the mining licence after the non-disclosure agreement with Kleros had expired in 2017. Kleros initiated arbitration proceedings, alleging that Tata Power had breached the non-disclosure agreements by misusing confidential information and acting in bad faith to exclude Kleros from the project.

Also read | Tata Power loses challenge to $490 million arbitration award

Tata Power to appeal against dismissal

The Singapore International Commercial Court has now rejected Tata Power's challenge to the quantum of damages earlier awarded to Kleros, as well as its argument that the majority arbitral order breached natural justice, according to an order delivered Wednesday, as quoted by Bloomberg.

Tata Power in its exchange filing released on Wednesday, said it has 28 days to appeal the decision of the Singapore International Commercial Court to the Singapore Court of Appeal. The company said it will be filing an appeal against the decision of the Singapore International Commercial Court within this time period.

Tata Power shares lost more than 6% in a week and nearly 7% in a month, overall declining around 8% in 2026 so far. The shares of the Tata Group company have fallen around 7% in one year.

In the longer term, Tata Power shares jumped 43% in three years and delivered multibagger returns of 177% over five years. The company has a market capitalisation of Rs 1.12 lakh crore.

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