[The role of the court system in regulating health insurance plans in Brazil].

Consumer complaints against private health insurance plans and companies in Brazil have become increasingly frequent in the country's 'supplementary' (non-public) health care sector, with numerous cases reaching the courts. The problem raised the need for regulation of this private market, which began in 1998, through Law no. 9.656. One of the challenges faced by the National Agency for Supplementary Health Care (ANS) is resistance to the legislation by health insurance companies, besides the fact that there are still some contracts not covered by this law. The objective of the current study was to analyze health insurance policyholders' appeals against court rulings for or against injunctions concerning coverage, in cases heard by the courts in Rio de Janeiro and São Paulo. The main data investigated were: court issuing the ruling; defendant; basis for the case; ruling by the Circuit Court and Court of Appeals; and the legal arguments. Based on the findings, the Brazilian court system still plays an important role in hearing and ruling on complaints by health insurance policyholders. The ANS has an important role in filling some gaps that have still not been solved in regulating the health insurance industry.