Dunnhumby's US operation is a joint venture with Kroger, a group that owns a range of store formats in several states. These include convenience stores, the format with which Tesco is set to launch on the West Coast in 2007.
The data analysis firm was approached by Kroger in 2002 to recreate the success of Tesco's customer database, and now 40% of US households own one of Kroger's loyalty cards.
However, Dunnhumby's main backer is Tesco, which took a controlling stake in the company in 2001.
According to Martin Hayward, Dunnhumby's UK-based director of futures, there have not yet been any conversations about whether Tesco will use Clubcard in the US.
Tesco's surprise expansion plan was announced last Thursday, when it also revealed that it has appointed marketing director Tim Mason to run the US business.
Mason was pivotal to the development of Clubcard since the mid-90s when Clive Humby and Edwina Dunn introduced the retailer to customer data analysis.
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