A dataset of facial photos intended to recognise peoples' identities in photo albums prompted controversy for failing to gain the explicit consent of those in the images, and for uses beyond its original purpose.

An investigation by artist Adam Harvey found that the People in Photo Albums (PIPA) dataset included images of people in various personal and social settings, potentially infringing on their privacy and that, despite attempts to anonymise the data, the personal nature of the photos could make individuals identifiable.

In addition, the uses of the data appear to have gone well beyond its stated purpose of processing personal photo albums. For example, Harvey discovered that PIPA was used by China's National University of Defense Technology and Tsinghua University, as well as by many commercial and industrial organisations.

It has also been pointed out that PIPA's creators fail to mention the type of CC licence under which the photographs were used, despite some CC licences not permitting any type of re-use.

The controversy highlighted the need for researchers to gain the consent of people whose personal and biometric data they are using, and the need for clearer ethical guidelines and consent processes in the development of datasets.