Sun Pharma, which has hit big time with the $4-billion acquisition of Ranbaxy, could face a minor irritant in Hyderabad with an ongoing litigation between Daiichi Sankyo-Ranbaxy and Zenotech Labs.

Zenotech Labs, in which Ranbaxy held 45 per cent equity, was to be acquired by the Japanese major along with Ranbaxy. However, its open offer price to Zenotech led to problems, with the promoter of the later, Jayaram Chigurupati, challenging it and taking his case to the SEBI, Company Law Board and the courts.

Though the issue has prolonged, the promoter continues to hold his 25 per cent equity in Zenotech, a biopharmaceuticals firm. Of the 70-odd employees, a majority have quit.