Wall Street held mostly lower in a quieter end to a record-breaking week in which stocks scored their best winning streak in a quarter century. That record rally has flagged over the past two days. UnitedHealth (UNH) - Get UnitedHealth Group Incorporated Report led the Dow Jones Industrial Average's losses after the Department of Justice joined a lawsuit accusing the health care company of overcharging Medicare. The company reportedly overcharged "hundreds of millions— and likely billions—of dollars." Deere (DE) - Get Deere & Company Report exceeded first-quarter estimates and offered positive guidance. The agricultural equipment company anticipates full-year sales growth of 4%, higher than consensus of a flat reading. WebMD (WBMD) fluctuated after indicating it was open to selling itself. The online medical encyclopedia said it was looking into strategic alternatives, which could involve selling all or part of the company.