Securities and Exchange Board of India said on Monday that implementation of T+6 norms for book building issues and blackout on research reports has been deferred till further notice.

This decision to defer the implementation of these two norms has been taken to ensure a smooth transition, Sebi said in a release in Mumbai on Monday and added that all other amendments would stand effective.

The decision to defer the two norms follows representation from market players that infrastructure and software systems were required to be upgraded before shifting to T+6 (where T is the book closure date and trading is to commence on the sixth date), Sebi said.

The norms were amended to provide for a blackout period on research reports from a date 45 days immediately preceding the filing of draft offer document with Sebi and extending

upto 45 days after commencement of trading in relevant securities, it said.

Sebi, on August 14, had amended its Disclosure and Investor Protection guidelines.

Some of the other amendments pertain to having minimum net tangible assets of Rs 3 crore (Rs 30 million) to raise funds through public issues.