SocGen placed a 20 percent stake in ALD in a sale which was a test of investor appetite for a company that combines cars and financial services.

The deal values ALD at around 5.78 billion euros.

ALD offers leases to corporate clients which make monthly lease payments to cover financing, depreciation of the vehicle and the cost of various services, such as tyre maintenance or insurance, while the vehicle is still owned by ALD.

ALD, whose core clients currently include mid-sized companies, is targeting individual customers in Europe who are increasingly turning to leasing or sharing cars, rather than owning them.

ALD expects to expand its business with individual clients to around 1 million cars in their fleet by 2025.

It aims to grow its fleet by 8 to 10 percent annually, up from the 1.4 million cars it had as of the end of March 2017.

"ALD's listing will provide extra flexibility to accelerate our expansion," the company's chief executive Mike Masterson said in a statement.

ALD said it is ranked number three globally and number one as a car leasing company in Europe by number of vehicles under management.

Along with European rivals, ALD faces some uncertainties over the valuation of its fleet partly related to tighter emissions regulations. Diesel engine vehicles account for 80 percent of the group's fleet and 93 percent of the group's fleet in France.

The sale includes an over-allotment option, which if taken into account would increase the size of SocGen's stake sale to 23 percent, raising 1.3 billion euros.

(Reporting by Maya Nikolaeva; Editing by Edmund Blair and Jane Merriman)