The Privacy and Electronic Communications Regulations (PECR) are derived from the e-privacy Directive 2002/58/EC, which aims to protect the privacy and confidentiality of users of electronic communications services. The PECR cover various aspects of electronic marketing, such as the use of cookies, unsolicited communications, and traffic and location data. According to the PECR, the following marketing-related activities require the consent of the user or subscriber, unless certain exemptions apply:
The use of cookies or similar technologies to store or access information on the user's device (Regulation 6).
The sending of electronic mail for direct marketing purposes to individual subscribers who have not given their prior consent (Regulation 22).
The making of unsolicited calls for direct marketing purposes to individual subscribers who have registered their number with the Telephone Preference Service or who have objected to such calls from a specific caller (Regulation 21).
The sending of unsolicited communications for direct marketing purposes by means of electronic mail, fax, or automated calling systems to corporate subscribers, unless they have indicated that they do not wish to receive such communications (Regulation 23).
Therefore, among the four options, the one that is least likely to be covered by the provisions of the PECR is the advertisements passively displayed on a website, as they do not involve the use of cookies, the sending of unsolicited communications, or the processing of traffic or location data. However, such advertisements may still be subject to other data protection laws, such as the GDPR, if they involve the processing of personal data of the users.
Reference:
PECR
e-privacy Directive
ICO guide to PECR