The Carlyle Group is set to have a bid in Asia scrutinised by authorities for the second time this year, after Taiwan's financial regulator said the US buyout firm may have broken market rules with its potential $5.7bn (€4.3bn) bid for domestic firm Advanced Semiconductor Engineering.

Bloomberg reports that Taiwan's Financial Supervisory Commission said Carlyle should have informed the authorities before announcing its potential bid for ASE. A spokeswoman said the regulator would investigate whether there had been any insider trading.