  This paper explores tracking and privacy risks on pornography websites. Our
analysis of 22,484 pornography websites indicated that 93% leak user data to a
third party. Tracking on these sites is highly concentrated by a handful of
major companies, which we identify. We successfully extracted privacy policies
for 3,856 sites, 17% of the total. The policies were written such that one
might need a two-year college education to understand them. Our content
analysis of the sample's domains indicated 44.97% of them expose or suggest a
specific gender/sexual identity or interest likely to be linked to the user. We
identify three core implications of the quantitative results: 1) the
unique/elevated risks of porn data leakage versus other types of data, 2) the
particular risks/impact for vulnerable populations, and 3) the complications of
providing consent for porn site users and the need for affirmative consent in
these online sexual interactions.
