Spain's National Court said Tuesday it had dropped its investigation into the country's top banker _ Banco Santander chairman Emilio Botin _ and 11 of his relatives over possible income and wealth tax evasion.

The case focused on tax returns filed between 2005 and 2009 on accounts the family held in Switzerland's HSBC Private Bank (Suisse).

The court said the probe showed the Botin family had normalized its tax situation before the investigation was opened last year.

Representing the Botin family, Madrid law firm Uria Menendez said the dismissal confirmed "what we said when the case was opened in June, 2011: that the family had voluntarily and completely regularized its tax obligations, which were and are all up to date."

Back then, the family said it had paid around (EURO)200 million ($255 million) in back taxes to normalize the situation.

The family said the accounts stemmed from assets that Botin's father held outside Spain at the time of his death in 1993,

Spanish tax authorities had learned of the accounts from French authorities, following a leak of the account details of 24,000 HSBC Private Bank (Suisse) clients from around the world.

Banco Santander S.A. is Spain's largest bank and the eurozone's biggest by market capitalization.