The placing of just under 31mln ordinary shares was announced overnight by Invesco Asset Management on behalf of its discretionary managed clients.
AJ Bell is not due to receive any proceeds from the placing.
The stake was a legacy of Neil Woodford's time at Invesco, when he bought 15% of then-private AJ Bell in 2007 for £78mln, eventually upping its holding above a quarter of the fund supermarket business, which floated at 160p in late 2018.
On Friday it was confirmed that the shares were sold by broker Numis at a price of 400p apiece to institutional investors, raising £124mln gross and leaving Invesco with a holding of 1.3mln shares or 0.3% of the group.
AJB shares, which had been trading at 450p earlier in the week, fell 14% to 382p in morning trade.