Form B 21 is a national form that implements the federal law requiring a debtor to submit a statement under penalty of perjury setting forth the debtor's Social Security number. Creditors in a case, along with the case trustee and United States trustee, will receive the debtor's full Social Security number on their copy of the notice of the meeting of creditors. The copy of that notice, which goes into the court file, will show only the last four digits of the number.