How does a facility become eligible to be considered for a classified bid or quotation?

Question 4 on the DSS Facility Clearance Process FAQs says this on the subject:

The same process used in the case of an unclassified procurement is involved. The facility must qualify as a bidder to a Government procurement activity or to a prime contractor or subcontractor performing on a Government contract. If the bid or potential subcontract involves access to classified information, the procuring activity or cleared prime contractor submits a request to clear the prospective bidder. Personnel from the Facility Clearance Branch at Defense Security Service (DSS) evaluate the request and assure that the request is valid. Part of this validation includes confirmation that the facility has a reputation for integrity and lawful conduct in its business dealings. Further, the contractor and its key managers must not be in a “barred” status from participating in Government contracts.

Here’s the link to the page:  http://www.dss.mil/isp/fac_clear/per_sec_clear_proc_faqs.html