MUMBAI: Markets regulator Sebi is open to making changes to the closing auction session (CAS) system, but it will not abandon it completely, Tuhin Kanta Pandey, chairman, Sebi said Monday. The top markets regulator also said that currently Sebi officials are analysing trading data for CAS, and are also going through suggestions and feedbacks from market players and on social media.Pandey said that the regulator is working on having a revamped securities lending & borrowing mechanism (SLBM) in place. He said a committee is working on this but declined to give any timeline for the same. Both CAS and SLBM are market mechanisms that are well entrenched in several developed markets. While SLBM has been in India for over two decades, itโs yet to take off in a big way. CAS, a tested-way to arrive at the closing price of a stock in those developed markets, was introduced here on Aug 3.Since its introduction, a large number of traders have been voicing their concerns, claiming that because of CAS, they have been suffering huge losses, especially while trading options. On the other hand, large institutions have been making money at their expense. One of the main grievances among traders is that thereโs a huge price variation between 3.15 pm, when regular trading stops to shift to CAS and 3.30 pm, when the post-CAS price is finally announced by the exchanges.โCAS is here to stay for sure, we will only see if there are certain constraints or issues that we can improve upon,โ Pandey said. He was speaking to reporters on the sidelines of a cybersecurity event at National Institute of Securities Markets.