Kishore Chhabria is planning to add a sweetener to his open offer for a 20 per cent stake in Herbertsons by paying an interest of 15 per cent per annum since 1995 to all subscribers.

The Special Appellate Tribunal had asked him to pay an interest to only those shareholders who have held the stock since 1995.

Such shareholders were entitled to a payment of Rs 120 per share over and above the offer price of Rs 90.50. This would have meant a total price of Rs 210.

"The plan is now to extend it to all shareholders so that the offer price becomes Rs 210.50 for all category of shareholders," sources close to Chhabria said.

This sweetener is likely to impact around 10 per cent of the shareholders of Herbertsons. The sources had earlier indicated that more than 90 per cent of the existing shareholders of Herbertsons are of 1995 vintage.

UB group officials said that this would have little impact as the Mallya offer is substantially better than Chhabria's.

UB group officials have been arguing that Chhabria's open offer price is just Rs 90.50 and the remaining Rs 120 is the interest component.

Their contention is that while the participants will just pay 10 per cent capital gains tax on Rs 90.50, they will have to pay an additional 30 per cent income tax on the interest component of Rs 120 which translates into Rs 36.

The final price in Chhabria's offer, therefore, even after excluding the capital gains tax component, works out to Rs 174, making it lower than Mallya's offer price of Rs 200 a share.

Meanwhile, on Monday the Supreme Court will hear Mallya's petition against the original SAT order, which had asked Chhabria to make an open offer for Herbertsons.

Mallya's earlier appeal in SAT to review its decision had been turned down.

Herbertsons owns the country's largest-selling whiskey brand, Bagpiper. It's 100 per cent subsidiary, BDA Distilleries, owns the hugely popular Officer's Choice brand.