Alumina says not aware of any information about speculated bid for partner Alcoa by BHP Billiton or Rio Tinto. Notes recent speculation, but has no information to explain recent share price gains. Shares up 1% after adding 5.9% yesterday after UK's Times newspaper reported both BHP and RIO were eyeing separate deals for Alcoa. Alumina also says has no information about speculation it could be private equity target.