(Bloomberg) -- Abu Dhabi National Oil Co. has increased its takeover offer for Covestro AG to about €11 billion ($12.4 billion) as it seeks to convince the German chemical producer to enter talks, people familiar with the matter said.Most Read from BloombergSingapore Passport Is World’s Most Powerful, Replacing JapanTesla Investor Rode a 14,800% Gain Thanks to 27-Year-Old AnalystMassive US Oil Caverns Sit Empty and Will Take Years to RefillTokyo Heat Smashes 150-Year Trend as Extreme Weather Bak