The firm will be renamed Ostrum Asset Management from 3 April.
Ostrum, which manages £290.8billion in assets, will focus on core investment capabilities, fixed income, equity and insurance.
Jean Raby, chief executive of Natixis Investment Managers, said: “Ostrum is our largest affiliate, and its distinct brand name re-affirms its key role in Natixis Investment Managers’ multi-affiliate structure.
“Ostrum’s Latin roots pay tribute to the company’s European origins, while its meaning ‘purple colored’ connects firmly to its parent companies Natixis and Groupe BPCE.
“The logo’s exponential symbol embodies Ostrum’s ambition to expand in partnership with its clients and staff, creating new opportunities in the fast changing asset management industry.”
Matthieu Duncan becomes chief executive of Ostrum, which has assets under management of £290.8billion.
He said it will be renewing its focus on its long-standing fixed-income experience, its focused equity capabilities and its insurance expertise.
The firm said it will continue to roll out alternative solutions, such as CLOs and private debt on real assets, while bolstering its equity investment expertise, including thematic, small & mid cap and emerging funds.
Ostrum will rely on Natixis’s global distribution platform, as well as the Groupe BPCE retail banking networks, to drive its growth.