The retail bank Sovereign and its parent company Banco Santander S.A. were liable for investor losses arising from Ponzi schemes, according to a pair of federal lawsuits filed recently. In the lawsuits, plaintiffs claim that Sovereign and its parent failed to take precautions to guard investors from funds that operated as Ponzi schemes. The cases are Inversiones Mar Octava Limitada v. Banco Santander, No. 1:09-cv-20215, (S.D.Fla.); Fine v. Sovereign Bank, No. 1:06-cv-11450 (D. Mass.).