It’s challenging enough for most people to manage and understand one insurance policy, so we sympathize with your situation. However, with all of the uninsured people in this country, don’t you feel a bit guilty having three health insurance policies (joking)? Coordination of benefit laws are at the state level. In Iowa, they are part of the Insurance Division Code 191, Chapter 38. Here is a direct link to the law: www.legis.state.ia.us/ACO/I..
. By the time you read through and understand this law, you might be in need of coordinating benefits for the treatment of a nervous breakdown. — June 30, 2009 @ 2:19 pm

Coordination of benefits is handled as part of state insurance regulation. Model coordination of benefits rules are put out by the National Association of Insurance Commissioners (NAIC). The NAIC rules are model rules, which states are free to adopt or ignore, but most states have rules similar to the NAIC rules, and most insurers follow rules that are similar. Massachusetts generally follows NAIC rules, with some exceptions that are probably not relevant, but the first place to look for guidance is in the Blue Cross Evidence of Coverage for your plan, which should cover basics of how Blue Cross coordinates benefits. If you feel that Blue Cross is not following its own rules, call their member service line and complain about how your claims were handled. If you are not satisfied with the resolution of the complaint, you should be able to appeal the company's decision. If nothing else, this will give you a clearer answer about how the claims were processed and why the company took the action it took. A link to Massachusetts COB regulations is below.

Source: http://www.mass.gov/Eoca/do...