HSBC Holdings plc, originally incorporated in England and Wales,[20] was a non-trading, dormant shelf company when it completed its transformation on 25 March 1991[3] into the parent holding company to the Hongkong and Shanghai Banking Corporation Limited now as a subsidiary, in preparation for its purchase of the UK-based Midland Bank and the impending transfer of sovereignty of Hong Kong to China. HSBC Holdings' acquisition of Midland Bank was completed in 1992 and gave HSBC a substantial market presence in the United Kingdom. As part of the takeover conditions for the acquisition, HSBC Holdings plc was required to relocate its world headquarters from Hong Kong to London in 1993.[21]