Mumbai: Billionaire investor Rakesh Jhunjhunwala is being probed by Sebi for alleged insider trading in the shares of Aptech Ltd, an education firm owned by him and family, said two people familiar with the development.The markets regulator is also investigating the role of other family members who are shareholders, as well as some board members, including investor Ramesh S Damani and director Madhu Jayakumar, the persons added.ET couldn’t ascertain the details of the Sebi probe, such as the period during which the alleged trading took place or the information based on which it was carried out. In its notice to Jhunjhunwala and others, the regulator has sought cooperation in its investigation.Besides Jhunjhunwala, wife Rekha, brother Rajeshkumar and mother-in-law Sushiladevi Gupta were called for questioning by Sebi on January 24. Jhunjhunwala appeared before Sebi’s investigating officer and was questioned for at least a couple of hours at the regulator’s headquarters in Mumbai’s Bandra-Kurla Complex.Jhunjhunwala, along with his lawyers, told the investigating officer that he was representing his family.Jhunjhunwala’s sister, Sudha Gupta, was called for questioning on January 23. Ushma Sheth Sule, sister of Rare Enterprises CEO and Aptech director Utpal Sheth, has been asked to appear for questioning on January 28. Rare Enterprises is Jhunjhunwala’s asset management firm.Jhunjhunwala, often referred to as India’s Warren Buffett for his ace stock-picking skills, is one of the country’s richest individual investors, holding shares worth almost Rs 11,140 crore, according to Bloomberg estimates. He first bought into Aptech in 2005 at Rs 56 a share. Since then, his stake — along with his family members — has risen to 49% with a market value of Rs 690 crore based on Aptech’s closing price of Rs 173 on the BSE on Monday. Aptech is Jhunjhunwala’s only investment where he wields management control.In response to an emailed query, Jhunjhunwala’s office called to say that he and his wife had “no comments” to offer. His brother Rajeshkumar, in an emailed response, also said he had no comments to make. Sushiladevi Gupta, Ramesh Damani , Madhu Jayakumar, Sudha Gupta, Ushma Sheth Sule, Aptech and Sebi didn’t respond to emailed queries.Also summoned by Sebi on January 20 were Rare Enterprises’ employee Amit Shah and Geojit Financial Services’ Satish Anam. Shah and Anam didn’t respond to queries. Geojit’s role in the affair is not clear as of yet. This is not the first time Jhunjhunwala has come under Sebi’s scanner. The regulator had questioned him in 2018 for suspected insider trading in Geometric, which is now a part of HCL Technologies. Jhunjhunwala later settled the case through consent by paying Rs 2.48 lakh. Consent is a mechanism through which alleged violations can be settled by paying a fee to Sebi without admission or denial of guilt.