Is it illegal to sell [i]triple[/i] vodkas in a bars/clubs?

[Mr Sparkle]

In a discussion at work yesterday I was informed that it is illegal to sell more than a double measure in any single glass, ie. if a customer was to order a triple vodka you are obliged to divide it between two glasses. Given that the people I work with are mostly stupid and often drunk themselves I called bullst on this. Was I correct in thinking that they had invented that rule themselves or is there indeed some unusual limit to the number of shots that can be pored into any one glass given that the alcoholic content can vary from 15 to 40% ABV.

I know it's a silly question but I have found nothing on Google.

ETA: We do sell mixers/pitchers of drink that contain more than 2 measures of spirit but these are intended for sharing.

Edited by Mr Sparkle on Wednesday 27th July 07:15

[Mr Sparkle]

Red Devil said:

I think the reason you can't find anything is because it is a matter for the discretion of the licencee, not by any Act or Statutory Instrument.

That's what I thought, albeit a policy made up on the spot (the manageress was drunk at the time of saying), a few people at work don't recognize the difference between law and branch policy, but you never know what 18th century rules no-one has gotten round to repealing yet.