With an aim to rein in insider trading by promoters without investors' knowledge, Sebi has decided to make it mandatory for all promoter entities to disclose any considerable purchase or sale of shares by them.

The decision would remove a major anomaly from the Sebi's insider trading prohibition regulations, which currently requires only directors and senior officials to disclose their dealings in the company share.

As per the Sebi board decision, it will be mandatory for the promoters and those part of the promoter group of a listed company to give the initial disclosures relating to their shareholding at the time of becoming promoter or part of promoter group.

Besides, they will have to make continuous disclosures whenever there is a change in their holdings exceeding Rs five lakh in value or 25,000 shares or 1% of total shareholding or voting rights, whichever is lower.

Similar, disclosures are at present required to be made by the directors and officers of the company.

"Till date Promoters of Companies were outside the purview of Disclosures under Insider Trading law unless they hold some managerial position," Consultancy firm Corporate Professionals' MD Pavan Kumar Vijay said.

"This was a big anomaly and inclusion of Promoters into the class of person is a welcome change," he said, adding that it was "hard to assume that Promoters are ignorant of price sensitive Insider information."

So far, promoters have been kept out of the regulations on the ground that they were not necessarily in the know about day-to-day business of their company, unless they held some positions with the company.

Sebi's former Executive Director and a legal expert on financial regulations Sandeep Parekh also said that a disclosure loophole has been filled by the regulator with this decision.

"This was a disclosure loophole which has been filled," Parekh wrote on his blog.