Tim Ryan was named CEO of Natixis Investment Managers effective April 12, replacing Jean Raby.
Mr. Raby has decided to pursue another professional opportunity. A spokeswoman said there were no further details to share at this stage.
Mr. Ryan was also appointed as a member of parent firm Natixis' senior management committee in charge of asset and wealth management.
"I would like to warmly thank Jean Raby for his remarkable work over these past four years," said Nicolas Namias, CEO of Natixis and chairman of the board of directors of Natixis Investment Managers, in a news release.
Mr. Raby will remain with the firm over the coming weeks to ensure an efficient transition to Mr. Ryan, the spokeswoman said. Mr. Ryan will be based in Paris.
"As we prepare to launch our new strategic plan for the period to 2024, I am delighted to welcome Tim Ryan to drive forward our robust momentum across our asset and wealth management businesses, develop our multiaffiliate model to serve our clients and enhance our ESG strategy," Mr. Namias added. "Tim Ryan's in-depth knowledge of the asset and wealth management businesses, together with his international experience, leadership and business development skills, will be key advantages for Natixis and our group."
Natixis Investment Managers has almost $1.4 trillion in assets under management.
Mr. Ryan was CEO of Generali Group's asset and wealth management unit. He was replaced by Carlo Trabattoni in March.