HSBC Holdings (HSBA.L), Europe’s biggest bank, said it has started a review of whether to move its headquarters out of Britain following regulatory and structural changes in the industry. Shareholders have urged the bank to consider moving its headquarters to Asia, probably back to Hong Kong, due to a hefty UK bank tax and other costs associated with being based in London. “The board has therefore now asked management to commence work to look at where the best place is for HSBC to be headquartered in this new environment,” said HSBC Chairman Douglas Flint on Friday.