CLIA (Clinical Laboratory Improvement Amendments) defines the regulatory standards for clinical labs which take in samples and perform medical tests on them. It works very differently from FDA drug or device approval. Most often the certification is done by an organization such as the College of American Pathologists (CAP), which scrutinizes a lab's protocols and output.
In any case, if they are CLIA-certified they are open for business, legally speaking.
Are there others?
Edit: Here's some background: http://www.leagle.com/decision/In%20FDCO%2020121203541