Exclusive - India's Lupin, U.S. firms weigh bids for GSK's mature drugs: sources

LONDON/MUMBAI (Reuters) - Indian generics firm Lupin , some U.S. drugmakers looking for a tax-saving deal in Europe and private equity funds are planning to bid for a range of older drugs being auctioned by GlaxoSmithKline (GSK) , five sources familiar with the matter said.