Woodford Equity Income Fund and Woodford Patient Capital Trust have become shareholders.
The investment includes £13m by CF Woodford Equity Income Fund, and £8m from Woodford Patient Capital Trust.
Invesco Asset Management, the largest institutional shareholder, has also topped up its holding.
Andy Bell, chief executive of AJ Bell, said: “I am delighted to welcome the Woodford funds as AJ Bell shareholders and thrilled that Invesco is maintaining its significant holding. The investment from these blue-chip institutions signals the exciting opportunities that are emerging.
“A new chapter in our growth story has started as the AJ Bell Investcentre platform benefits from advisers and their clients embracing pensions’ freedoms. In addition, 2015 will see us continue to invest heavily to enhance the platform’s award-winning tools and functionality.”
A statement from AJ Bell today read: “Shares were made available by management and existing shareholders. Funds managed by Invesco Asset Management Limited, the largest institutional shareholder, did not sell any shares and took the opportunity to top up their holding by a modest amount.
“No new shares were issued in the transaction and employees, led by Andy Bell, chief executive, remain the single largest shareholder group.”
In the six months to 31 March 2015, AJ Bell said that it had increased retail customers by 7% to 111,503, contributing to assets under administration rising 10% to £26.1 billion and representing record first-half AUA growth of £2.4 billion.
The platform attributed further growth to the pension reforms, saying these have driven inflows from private investors and their advisers seeking low-cost, easy-to-use investment platforms.
Shore Capital Stockbrokers acted as broker in this share transaction.