German to English Bus/Financial Medical: Pharmaceuticals

I came across this term while translating for a large pharmaceutical company:

Lohnlabore unterliegen den gleichen Anforderungen wie zuvor für Lohnhersteller beschrieben.

Although I am unfamiliar with the term, I am guessing that "Lohn" in this case refers to "contract work".
My web research didn't yield any direct results for "Lohnlabor", however for the terms "Auftrags-/Vertragslabor" I found the translation "contract laboratory".

Are these terms synonymous?
Just thought i'd check to make sure.

Thanks!