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Algorithm::CheckDigits::M10_008(3pm) User Contributed Perl Documentation Algorithm::CheckDigits::M10_008(3pm)


CheckDigits::M10_008 - compute check digits for Sedol (GB)


  use Algorithm::CheckDigits;
  $sedol = CheckDigits('sedol');
  if ($sedol->is_valid('0123457')) {
        # do something
  $cn = $sedol->complete('012345');
  # $cn = '0123457'
  $cd = $sedol->checkdigit('0123457');
  # $cd = '7'
  $bn = $sedol->basenumber('0123457');
  # $bn = '012345'


Prior to March 2004 SEDOL codes solely consisted of numbers. Since March 2004 SEDOL codes are a 7 character alphanumeric code.

The structure of the alphanumeric SEDOL codes is one alpha character followed by 5 alphanumeric characters followed by the numerical check digit.

No SEDOL code will be issued without the first alpha character. Active numerical SEDOL codes issued prior to March 2004 remain valid.


All characters are assigned a numerical value from 0 to 35 where the characters '0' to '9' get 0 to 9, 'B' to 'Z' get 11 to 35 with the position of the vowels kept empty (for instance 'D' gets 13, 'F' gets 15).
Beginning left all numbers are weighted with 1,3,1,7,3,9 and 1 (checkdigit)
The sum of all products is computed.
The check digit is the difference of the sum from step 3 to the next multiple of 10.


Returns true only if $number consists solely of numbers and the last digit is a valid check digit according to the algorithm given above.

Returns false otherwise,

The check digit for $number is computed and concatenated to the end of $number.

Returns the complete number with check digit or '' if $number does not consist solely of digits and spaces.

This function always returns the SEDOL code in upper case.

Returns the basenumber of $number if $number has a valid check digit.

Return '' otherwise.

This function always returns the SEDOL base number in upper case.

Returns the checkdigit of $number if $number has a valid check digit.

Return '' otherwise.


None by default.


Mathias Weidner, "<>"


perl, CheckDigits, Masterfile technical specifications V7.0.

2021-11-17 perl v5.40.0