Westpac has officially offloaded its final stake in its once wholly owned subsidiary Pendal, ending a 20-year dalliance and leaving the ASX-listed fund manager a "stand-alone independent business on a global scale".

Australia's oldest bank on Thursday confirmed it had completed the sale of its residual 9.5 per cent stake in Pendal to undisclosed institutional investors, in a $184 million transaction foreshadowed by The Australian Financial Review's Street Talk column. Shares in Pendal fell 2.01 per cent to $6.10 in Thursday's trade.