The acquisition will expand company’s offering for investors seeking exposure to core fixed income and municipal bond products.

Natixis chief executive officer Pierre Servant said, "Bringing McDonnell’s fixed income and municipal bond expertise into the NGAM family is a positive step toward fulfilling a critical need for clients who are focused on durable portfolio construction."

As a new NGAM affiliate, McDonnell will retain its brand name and suburban Chicago headquarters and continue to operate autonomously with no change in management or professional staff.

The current professional team of investment advisor will carry out activities based on the same investment philosophy and process on behalf of clients, and market services through existing distribution channels.

NGAM has plans to launch a new municipal bond product in early 2013.

As of 30 September 2012, McDonnell had approximately $13.5bn in assets under management for institutions and individuals.