ARLINGTON, Va. – The U.S. ATM and EFT landscape has shifted again as Wells Fargo bank announced that it has dropped MasterCard's Cirrus network to process its ATM transactions, in favor of Visa's Interlink. This has raised questions about the bank's agreements with the STAR network, which is owned by Concord EFS. Press reports indicate that Concord's STAR network and Wells Fargo are still negotiating the contract renewal for processing debit transactions that require a personal identification number. Concord's STAR has already lost two large bank customers, Wachovia and U.S.Bancorp, and it is unclear how the possible loss of Wells Fargo would change the scene for its pending merger with Denver based First Data. Some analysts have suggested that it could make the deal more likely because it could reassure federal anti-trust regulators that a pending merger between Concord and First Data would not suck all the competition out of the market in PIN debit processing. However, the loss of big STAR customers could make the merger less attractive from First Data's point of view, but some analysts have estimated that First Data would have built the possible loss of Star customers into its calculations previously. The merger between Concord and First Data has been estimated to leave the merged company in control of between 75% and 80% of the PIN debit market. Some groups that have objected to the pending merger have cited the control the new firm could exert on the ATM and pin debit processing market.