I recently found out I was sent to a collection agency (this is 5/31/2012) for a medical bill that was never paid as a result of a medical provider never being paid and the date of service was 1/3/2007 ! I paid the bill in full last week after never even knowing it existed. Isn't there some type of drop dead date for a provider to bill a patient. Also I have both blue shield and medicare, the cost to be would have been nothing. This took place in a hospital that had my medical insurance information.

There is a Statute, a date beyond which a debt cannot be collected legally.

What State?

Correct but since you paid the bill the statute no longer applies. Where are you located?

... Also i have both blue shield and medicare, the cost to be would have been nothing. ...

Have you requested that your insurance reimburse you?