ITM has acquired the products and assets of Profund Solutions from Mercer.
The firms will collaborate to create a "platform of scale" in the pensions industry, offering a broad range of capabilities to deliver value to clients and across the entire pensions market.
The acquisition will also provide ITM with new offshore development and support capabilities to enhance the firm's scale and delivery functions.
Profund Solutions has a client base of more than 100 third-party administrators (TPAs) and individual schemes.
The acquisition of Profund further strengthens ITM's position as a strategic partner for pension schemes and TPAs, continuing to support the firm's vision of "delivering a rich set of enhanced independent data and administration management software and data-driven platform solutions for both defined benefit and defined contribution schemes".
ITM chief executive Mark Lecompte said: "Profund is a highly-regarded brand providing quality end-to-end pensions administration and accounting software to third-party administrators and in-house pension scheme administrators. Its long-standing presence and loyal customer base make it the perfect strategic fit for ITM's expanding business and solution strategy."
Profund Solutions chair and Mercer UK pensions administration leader Malcolm Reynolds said: "We are pleased to see ITM acquire the Profund administration software business. ITM plans to further strengthen and secure the long-term success of Profund, to the benefit of its clients and people. This agreement allows Mercer to focus on optimising our portfolio of solutions across health, wealth and career."
Inflexion (ITM's major shareholder) portfolio manager Andrew Mainwaring added: "ITM is a clear leader in its space, with a strong reputation, bespoke proprietary software and long-term relationships with blue-chip customers.
"The acquisition provides an excellent opportunity to consolidate pensions software assets and to deliver further complimentary services to a larger customer base."