Banco Santander, Spain's biggest bank and the largest shareholder in First Union Corp., revealed Thursday it is selling its entire stake.

In a filing with the Securities and Exchange Commission, Banco Santander disclosed it was selling 44.7 million First Union shares.

On Aug. 5 Banco Santander reduced its holding in First Union to 7.12% from 7.96% and said it did not intend to sell any more shares. The bank said in a statement at the time: "We remain a satisfied, long-term investor in the company."

Banco Santander got its stake in First Union by investing in New Jersey's First Fidelity Bancorp., which sold to First Union in 1996.

"While our initial investment made in 1991 in First Fidelity was a strategic move for us, our current investment in First Union is not strategic in nature," said Banco Santander chairman and chief executive officer Emilio Botin.

He added: "We have the utmost confidence in First Union's ability to continue to generate exceptional returns for its investors."

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