JPMorgan entity among two firms barred in India over alleged closing auction manipulation

CAS, which was introduced in India on August 3 to improve price discovery, is a 20-minute auction window that starts at 3:15 p.m. IST after regular trading ends.

In its first two weeks, the new mechanism, introduced to align with global practices, has triggered sharp swings in the Nifty 50 and BSE Sensex benchmarks, as well as in options contracts linked to the indexes.

"Any manipulation or unfair practices employed to disturb the fair discovery of prices in CAS has to be dealt with sternly by the regulator," SEBI said, adding that such conduct could "undermine the integrity of the CAS mechanism" and disrupt the orderly functioning of securities markets.

According to the regulator, CAS is transparent, making it easier to catch such manipulation.

The regulator, in an order issued within six days of the alleged manipulation, added that it had so far not found any evidence that the two firms acted together.