Shearman & Sterling has acted opposite Davis Polk & Wardwell on the $4bn acquisition of generic pharmaceutical company Ranbaxy by India's Sun Pharmaceutical Industries.

The deal, expected to close in December, will create the fifth-largest specialty generics company in the world and the largest pharmaceutical business in India, with 65 outlets and 47 manufacturing facilities across five continents.

Ranbaxy is currently owned by Japan's Daiichi Sankyo, Japan's fourth-biggest drugmaker by revenue, which took a controlling stake in the company in 2008.

Acting for Sun Pharmaceuticals is US firm Shearman & Sterling, with a team led by corporate partner Peter Lyons in New York.

The firm acted alongside Indian law firms Crawford Bayley & Co and SH Bathiya & Associates, while Citiand Evercore provided financial advice.

Davis Polk & Wardwell meanwhile represented Daiichi Sankyo and Ranbaxy, with New York-based global co-head of M&A David Caplan heading up alongside corporate partner Michael Davis.

Providing Indian advice to Daiichi was Amarchand & Mangaldas & Suresh A Shroff & Co, who acted as co-counsel to Ranbaxy in tandem with Luthra & Luthra Law Offices.

Leading a team at Amarchand was Mumbai-based managing partner Cyril Shroff alongside corporate partners Nivedita Rao in Bangalore and Gurpreet Vasir Ashar in Mumbai.

ICICI Securities was financial advisor to Ranbaxy while Goldman Sachs was appointed by Daiichi.

The deal marks Daiichi's retreat from India's drug market, but a significant step for Sun Pharmaceuticals in giving it a stronger foothold in the global drugs market.

Dilip Shanghvi, managing director of Sun Pharma said, "Ranbaxy has a significant presence in the Indian pharma market and in the US where it offers a broad portfolio of ANDAs and first-to-file opportunities.

"In high-growth emerging markets, it provides a strong platform which is highly complementary to Sun Pharma's strengths.We see tremendous growth opportunities and are excited with the prospects to create lasting value for both our shareholders through a successful combination of our franchises."

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