Natco stock surged 6.51 per cent to Rs 425.20 on BSE.
Similar movement was seen on NSE as the shares of the company climbed 6.85 per cent to Rs 424.90.
The board has approved sale of the US stores - a non-core business of the company, Natco Pharma had said in a regulatory filing yesterday.
The stores are owned by Natco Pharma Inc, a wholly-owned subsidiary of the company.