Why Banco Santander SA (SAN) Stock Is Down Today

NEW YORK (TheStreet) -- Banco Santander SA  fell Thursday as Portugal's Banco Espirito Santo's turmoil dragged down European financial institutions. Banco Espirito Santo shares were suspended from trading on Thursday after the stock dropped another 17%. Shares of the bank's controlling shareholder, Espirito Santo Financial Group SA, were also suspended "due to ongoing material difficulties" at Banco Espirito Santo, according to The Wall Street Journal. This week's nosedive took 32% off the b...