mumbai, Jan. 22 -- Foreign portfolio investors (FPIs), who have been selling Indian shares since October 2024, have also doubled down on their bearish derivatives bets to make a quick gain from these positions, which generate profits when markets fall. In addition to shorting Nifty and Bank Nifty futures, FPIs have begun selling Nifty and Bank Nifty call options in the past six months to gain from a fall in the indices, exchange data shows. A sale of a call involves the seller earning a premium from a buyer. If the market falls or stays flat, the seller gains; if it rises, the seller loses unless she owns the underlying stocks of Nifty or Bank Nifty. Futures facilitate a purchase or sale of an underlying stock at a fixed price on a future date. A call option gives a buyer the right to buy an underlying stock or index at a fixed price on a future date. The seller of the call is obliged to sell the stock or index to the buyer. While FPIs have cumulatively sold cash shares worth Rs.4.26 lakh crore since October 2024, they have extensively shorted Nifty and Bank Nifty futures contracts, reaching a record high cumulative net sell figure of 201,567 contracts on Tuesday, per NSDL and NSE data. Additionally, entities classified as FPIs have, in a departure from normal practice, increasingly resorted to selling call options on benchmark Nifty and Bank Nifty to gain from the downside since Nifty first soared to a record high on September 27, 2024, shows exchange data. For instance, alongside index futures shorting in the past 15 months, FPIs net sold index call options on 95 trading sessions over the past 313 sessions since the Nifty first hit a record of 26,277.35 on September 27, 2024. The sales picked up since July last year and have increased this year. In the preceding year, FPIs net sold Nifty calls only on 31 trading days out of 244 sessions, remaining buyers the rest of the time. Out of 13 trading sessions in January, they've net shorted calls on eight days. From the September 2024 high, Nifty plummeted 17% to a multi-month low of 21,743.65 on April 7. The index recovered 21% thereafter to test a new high of 26,325.8 on December 1, after a gap of 14 months, on account of heavy domestic institutional investor buying of Rs.5.99 lakh crore. However, relentless FPI selling amid a falling rupee dragged markets down to a low of 25,693.25 before they recovered to test a new high of 26,273.95 on January 5. But, fresh tariff tensions over Greenland, lack of clarity over consummation of a trade deal with the US, and a falling rupee soured sentiment among FPIs again, dragging the market down to 25,232.5 on Tuesday. This roller-coaster ride has enabled FPIs to gain from their net bearish call positions apart from the short futures bets. When they take fresh short positions on index calls, FPIs pre-empt a fall in the following sessions. "Such a significant shorting of calls is to profit from anticipated downside or flat markets by FPI prop desks who are using weekly options expiries to take very short term bets amid the external headwinds," said Kruti Shah, quant analyst at Equirus....