Shareholders of Caremark Rx, a pharmacy benefits manager, today approved a $26bn (€19bn) offer from its favored suitor even though the bid was opposed by the nation's largest pension fund.

Caremark shareholders accepted the final offer from drug store chain CVS, ending a contentious four-month battle by rival pharmacy benefits manager Express Scripts. CVS increased its offer three times in response to higher offers from Express Scripts. CVS shareholders voted in favor of the deal earlier this week.