Societe Generale SA, France's second-largest bank by market cap, and US wealth management company Rockefeller Financial Services Inc have teamed up for a global private banking venture.

Societe Generale bought a 37 per cent stake in Rockefeller Financial Services Inc, the parent of Rockefeller & Co., through SG Private Banking, as a part of the deal.

The two plan to work together to offer services to individuals and families with at least $30 million to invest.

The US has almost 40,000 ultra high net worth individuals, according to a report published last year by Cap Gemini SA and Merrill Lynch & Co.

The companies did not disclose the price of the deal, but said they would work together to "share areas of expertise and jointly serve the financial needs of ultra high net worth individuals and family offices around the world".

Reports quoting sources close to the situation said SocGen had paid "around $100 million" for the deal.

New York-based Rockefeller had $29 billion of assets under management as of 31 March. SG Private Banking has assets of around 71 billion euros ($109.1 billion).

SG Private Banking has about 71 billion euros under management, while New York-based Rockefeller oversees almost $30 billion. The French bank doesn't have an option to increase the stake.

This is second North American deal this year after SG Hambros division's acquisition last year of ABN AMRO Private Banking unit in Canada.

The deal comes less than five months after Societe Generale announced a 4.9 billion-euro loss in January, which the bank said was caused by rogue deals carried out by Jerome Kerviel, a junior trader at the bank.

Societe Generale was forced to raise 5.5 billion euros in a share sale to replenish capital after the loss and writedowns linked to the collapse of the US subprime market.

Societe Generale's private bank, created in 1997, employs more than 2,700 people in 25 countries, and  targets clients with more than 1 million euros.