Skin care products with a shelf life of less than 30 months have to be labelled with their shelf life date.
Skin care products with a shelf life of more than 30 months are not required to bear this information however need to show their period of use (after the first opening).
The period of use is specified with an open-jar symbol and the number of months it can be used after opening it for the first time, as for instance 3 M for 3 months.
Both shelf life date and period of use are based upon room temperature (25°C) and normal lighting conditions (no sun exposure!).
It makes sense to provide both indications on the labels even if this is not legally required.
Detailed information on the issue can be read in the following articles:
Dr. Hans Lautenschläger