Biotech firm Biocon Ltd
The company plans to sell 22 million shares, including an overallotment, it said in a statement, after the prospectus was filed with India's market regulator.
It gave no value for the stock offering, but local newspaper reports said the company could raise as much as Rs 600 crore ($95 million).
In January, Biocon sold 10% stake in Syngene for Rs 380 crore to IVF Trustee Company, valuing the group at Rs 3,800 crore, or just over $600 million.
Biocon had also said in January it would list Syngene by selling up to 15% of the unit through an initial public offer, but it had given no specific timeline.
The listing is expected to take place by July.
($1 = 62.9100 rupees)