The largest marketing-database companies in the U.S. include Acxiom, Alliance Data Systems Corp.

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Another company that Sakhrani says could be significantly impacted by the fee change is Alliance Data Systems.

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Other competitors in the financial sector include: Alliance Data Systems Corporation (ADS), MasterCard (MA), and American Express (AXP).

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Blackstone Group 's ( BX - news - people ) acquisition of Alliance Data Systems while selling the stock short.

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Among the largest underlying components of FAS, in trading today Alexandria Real Estate Equities, Inc. ( NYSE: ARE) is down about 2%, Alleghany Corp. ( NYSE: Y) is up about 0.5%, and Alliance Data Systems Corp. ( NYSE: ADS) is higher by about 0.5%.

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Will it be big, stand-alone (mostly) boxes by EMC, pure networking schemes like Network Appliance or hybrids from the new Hitachi Data Systems and Sun alliance?

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