As the purpose of signed documents are that they should include validation information, the signature certificate, including social security numbers of the signees, will accompany it when downloaded from the Admincontrol solution.
When it is required to share signed documents outside the Admincontrol solution where you do not want social security numbers to appear, the following approach is recommended; in your pdf program, open your signed document and choose print to file. Save the file to your chosen format (this could also be a pdf), this will then create a copy of the pdf without the signature information and without social security number. Please note that such a copy does not contain validation information in the document, and cannot be used for verification purposes.
It is also possible to choose print to pdf directly from the Admincontrol viewer, to save a copy of the signed document without the signature information and without social security number. Please note that such a copy does not contain validation information in the document, and cannot be used for verification purposes.