The FTC alleged that the acquisition would boost drug costs and inflate Medicare expenditures by consolidating the industry and reducing price competition.

The merger would have given Omnicare a 57% market share versus two percent for its nearest, non-PharMerica rival.

[citation needed] Starting in 2006, healthcare entrepreneur Adam B. Resnick sued Omnicare, a major supplier of drugs to nursing homes, under the False Claims Act, as well as the parties to the company's illegal kickback schemes.

Omnicare allegedly paid kickbacks to nursing home operators to secure business, which constitutes Medicare and Medicaid fraud.

Omnicare allegedly had paid $50 million to the owners (Leonard Grunstein and Rubin Schron) of the Mariner Health Care Inc. and SavaSeniorCare Administrative Services LLC nursing home chains in exchange for the right to continue providing pharmacy services to the nursing homes.