POS independent Labs

When a facility has an independent lab that accepts specimens from outside sources, not registered patients, what should be the correct Place Of Service for billing those specimen?
Should it be where the specimen is read @ the lab or the outside dr. office where the specimen is taken?

re: POS independent Labs

There remains a lot of confusion about this.

The guidance CMS has used most consistently for independent labs is to bill the POS where the sample was taken, though they have backed a bit away from that and said to await further guidance.

They have been pretty clear, at least for hospital patients, that the lab cannot bill the TC of the lab service for the hospital patient in cases where there is a technical and professional component.