Branding and trade mark use can change in subtle (and not so subtle) ways over time. For example, it may be used in a different typeface, a different colour or together with another device mark.
This creates a problem for trade mark holders as, in the EU if you have not used a trade mark for some of the goods and services for which is it is registered, once the initial 5 year grace period after registration is over, anybody may apply to revoke the trade mark on the basis that it has not been used. This revocation can apply to the whole or part of the trade mark.
This question is always a challenging one to answer but the EU Intellectual Property Network (EUIPN) has provided some extremely helpful guidance in their Common Communication published on 15 October 2020. This document includes the CP8 Common Practice and related information such as the implementation dates for the relevant IP offices across the EU. It is available in English here.
Key points to note:
the key question is always does the variation change the distinctive character of the mark. For example, adding a word mark below a device mark does not change its distinctive character but adding another image to a device mark may change its distinctive character.
marks which have a lower level of distinctiveness can be changed less than a more distinctive mark. For example, changing the colour of device mark for a purple banana to yellow is not enough to show use of the mark as registered.
even if you don't use all elements of a composite sign, it may still be sufficient to show use - this is particularly the case where the elements that are not used have a low level of distinctiveness
in general, there is more flexibility given to word marks than device marks (not exactly breaking news but a helpful reminder).
Whilst this document doesn't bind the UK intellectual property office (UKIPO), it is very helpful guidance and will no doubt be considered by the UKIPO when assessing use.