Did you get your full drink?
In Europe, you see it everywhere. A marking on a glass or beverage container showing a particular volume or measure. You also see a Conformité Européenne (CE) Mark on the beverage container.
It turns out that CE Marking if required by law if the beverage container is for a particular volume or measure.
On this McDonald's cup, the CE Mark says = CE M20 1259. And it breaks down as follows:
CE = Conformité Européenne (French for European Conformity)
Mxx = year when the CE mark was applied
yyyy = registration number for the notified body (organization designated by an EU country to assess the conformity of certain products before being placed on the market) that verified the CE marking