IDBI Bank has sold further 4,80,41,092 equity shares constituting 9.03 per cent of the paid up capital of Sidbi on September 26 and 27, IDBI Bank said in a regulatory filing.
However, the bank did not disclose name of the buyer.
Earlier this week, the bank sold one per cent stake in Sidbi.
Earlier this year, IDBI Bank had said it plans to dilute stake in some non-core businesses to shore up capital base.
Sidbi has earned profit of Rs 1,120 crore for the fiscal year 2016-17, marginally lower than Rs 1,177 crore earned in the previous fiscal year.
Sidbi was originally 100 per cent owned by IDBI, when it was a term lending institution. Later in 2000, it divested 51 per cent stake in favour of the government owned banks and insurance companies.