Banco Santander S.A.'s (NYSE: SAN) planned offering for its Mexican unit has garnered more than $6 billion in share orders, more than 1.5 times the size of the issuance, according to a Bloomberg report. Demand could increase as shares are still being marketed, according to anonymous sources cited by Bloomberg. The Madrid, Spain-headquartered bank was originally seeking to raise around $4 billion by selling about 25% ownership in the Mexico division.

Banco Santander's primary Spanish business has been suffering because of the European debt crisis. The Mexican unit's profits in contrast have been rising. Shares in Santander were trading moderately higher this morning in anticipation of a European bailout of Spanish sovereign debt.

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