The US Patent and Trademark office has received a patent application for an open source electronic medical record.
The application number is US 2004/0172307 A1 Publication date: Sept 2004.

I found the prior art differentiating factors particularly entertaining:

“(0012) The present invention addresses the limitations of the prior art in that the system in accordance with the present invention is Internet-based, patient-centered, patient-controlled, provider-funded and open source. This unique combination promotes acceptance by patients, physicians and institutions and allows all to experience the benefits of a complete, comprehensive, easily available and robust lifetime medical record.”

The searchable USPTO website is located here “http://www.uspto.gov/patft/index.html”:http://www.uspto.gov/patft/index.html