The open offer is being launched after an approval from fair trade watchdog Competition Commission for acquiring up to 36.56 per cent stake in Mangalore Chemicals and Fertilisers Ltd (MCFL) for Rs 398.2 crore.
Zuari, led by Kolkata-based industrialist Saroj Poddar, had announced a voluntary open offer in December last year as well for acquiring 25.9 per cent stake in MCFL.
In a regulatory filing today, Zuari group firm Zuari Agro Chemicals said the open offer will begin on April 20 and close on May 26.
The two-way battle is going on between Zuari Group and Pune-based Deepak Fertilisers for a long time for taking over MCFL.
At the end of December 2014, Zuari held 16.47 per cent stake in MCFL while Deepak Fertilisers had 29.05 per cent.
Crisis-hit UB Group, which had earlier supported Zuari offer, owns 21 per cent stake in MCFL.