Medicaid Third Party Liability Act This bill modifies requirements relating to Medicaid third-party liability. Current law generally requires legally liable third parties (e.g., health insurers) to pay claims before Medicaid. However, Medicaid must pay first (and seek reimbursement from liable third parties) for claims for (1) preventive pediatric care, and (2) services for an individual for whom child support enforcement is being conducted by the state. The bill repeals these exceptions. Current law also requires state Medicaid programs to take all reasonable measures to identify legally liable third parties. The bill specifically prohibits federal Medicaid payment for services to individuals for whom third-party insurance information was not obtained and verified by the state.