NEW YORK - Chemical Banking Corp. and shell Oil Co. announced their joint credit card on Monday, vowing to make it the largest cobranding effort yet.

Revealing the plan several months after its development had become an open secret, Chemical said it will initially market the Shell MasterCard to nine million people, including a third of the 12 million who have Shell's in-house card.

Subscribe Now

Access to authoritative analysis and perspective and our data-driven report series.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.