code: private boolean checkFrVatId(final String pvatId) {
      final int checkSum = Integer.parseInt(pvatId.substring(2, 4));
      final int sum = Integer.parseInt(pvatId.substring(4));
      final int calculatedCheckSum = (12 + 3 * (sum % MODULO_97)) % MODULO_97;
      return checkSum == calculatedCheckSum;
    }
docs: check the VAT identification number, country version for France.
  
  @param pvatId vat id to check
  @return true if checksum is ok