Thursday, 16 April 2009

Hidden Codes on Security Machins

Douglas Myall published the news yesterday that the non-denominated security Machins have a hidden code that identifies the format in which the stamp was issued. In other words, just by looking at a single stamp, you can tell if it came from a counter sheet, business sheet, booklet of four, booklet of six, booklet of twelve, or mixed definitive/commemorative booklet.

The code is a change of one letter in the curvy ROYAL MAIL pattern, located above the diadem.

The codes are as follows:

B replacing A in Royal - ROYBL MAIL - in business sheets of 50 (large 1st and 2nd Machins) [corrected April 19]

B replacing A in Mail - ROYAL MBIL - in business sheets of 100 (standard 1st and 2nd Machins) [corrected April 19]

C replaing A in Mail - ROYAL MCIL - in mixed booklets with four 1st Machins and two commemoratives ("C" is for custom)

F replacing R in Royal - FOYAL MAIL - in booklets of four stamps (large 1st and 2nd Machins)

S replacing A in Mail - ROYAL MSIL - in booklets of six (standard 1st Machins)

T replacing A in Mail - ROYAL MTIL - in booklets of twelve (standard 1st and 2nd Machins)

There are no hidden codes in counter sheets, which means that no denominated Machin has a code.

Royal Mail says that these codes let them know the source of a stamp when a problem is discovered, for example, a sub-standard application of the phosphor bands.

Myall is giving each of these stamps a separate number at level 3 in his Deegam Handbook. Users of the Handbook who have signed up for electronic download of his Deegam Reports can download the latest, DGR 82, at his web site, This issue shows the various codes and includes his catalogue listing and profiles.

UPDATE: Some images are here.

If you need a refresher on these new Machins, click here and here. Also this lengthy discussion on the Machin forum.



Ian - Norvic said...

I thought for one terrible moment that Doug was doing an April Fool trick on us, but no, chekcing this morning's post I find one DLR (Counter Sheet) stamp, and one Walsall 1st class, the latter identified as coming from a book of 12, by the T in MTIL at the top right corner. Oh wonderful! (NOT)

GBStamps said...


The first thing I did when I saw the Deegam report was to look to see if it was dated April 1. Really. FOYAL MAIL?

Then I, too, realized that Doug wasn't kidding.


GBStamps said...

Thanks to eagle-eyed Douglas Myall for catching my errors in describing the two B codes. These are now fixed.


Anonymous said...

Thanks to all the Machin experts for researching and reporting on this. While I have a Machin collection, I typically don't run out and just buy the new issues, but these changes are so interesting that I just ordered from RM the other day the full set of high value and each of the Security booklets. This will mean hours of fun peering into a 10x ...


Ian - Norvic said...

June's Philatelic Bulletin includes a new excuse for these from Royal Mail:

"Identifying a stamp's original format will help RM to correct any production issues which may arise, for example, problems reading the phosphor signal on the stamps."

Nice to know there's a genuine reason, then.