code: protected function contraAccountName(array $lines)
      {
          switch ($this->format) {
              case self::FORMAT_CLASSIC:
                  if (preg_match('/(\d{6})((?:C|D)R?)([0-9,]{15})(N\d{3}|NMSC)([0-9P ]{16}|NONREF)(.*)/', $lines[0], $match)) {
                      return trim($match[6]) ?: null;
                  }
                  break;
  
              case self::FORMAT_STRUCTURED:
                  if (preg_match('#/NAME/([^/]+)/#', $lines[1], $match)) {
                      return trim(str_replace("\r\n", '', $match[1])) ?: null;
                  }
                  break;
          }
      }
docs: Get the contra account holder name from a transaction
  
  @param array $lines The transaction text at offset 0 and the description at offset 1
  @return string|null