If you do not want your current employer contacted, you need to advise the Clearance Coordinator who contacts you regarding the completion of your SF-86, and/or annotate it on the SF-86 under that employment entry. While efforts will be made to  work with you before contacting any current employment references, it is required that your current employment is verified. The absence of an employment verification will result in your case being adjudicated without satisfying investigative standards. This may result in DS’s inability to consider your eligibility for access to classified information, and may compel DS to err on the side of national security and deny access to sensitive and/or classified information.