Article 5(2)(d)
Obligations for gatekeepers
"The gatekeeper shall not do any of the following:
[...]
(d) sign in end users to other services of the gatekeeper in order to combine personal data,
unless the end user has been presented with the specific choice and has given consent within the meaning of Article 4, point (11), and Article 7 of Regulation (EU) 2016/679.
Where the consent given for the purposes of the first subparagraph has been refused or withdrawn by the end user, the gatekeeper shall not repeat its request for consent for the same purpose more than once within a period of one year.
This paragraph is without prejudice to the possibility for the gatekeeper to rely on Article 6(1), points (c), (d) and (e) of Regulation (EU) 2016/679, where applicable."