The UK-based FNZ provides technology and service platforms to global banks, insurers and asset managers, and handles £50bn ($65bn, €56bn) in assets under advice.
The two private equity backers own two-thirds of FNZ with the rest owned by senior management.
Senior management are not expected to sell significant chunks of their stakes in the company. The sale process is expected to start before the end of the year, sources said.
Sources told Sky News that FNZ would be valued in any deal between £1bn and £2bn, with the upper end of the range described as “reasonable”.
In January, Aviva updated its platform by switching its technology provider to FNZ. However the update has caused major issues for advisers since then.
While in July, International Adviser reported that FNZ had acquired German platform Ebase which has €31bn in assets under administration.
FNZ was founded in Wellington, New Zealand in 2004 and offers an outsourced, wealth management platform service via the internet, which combines the software-as-a-service model with trade processing and asset custody.