An attorney says she saw her library reading habits reflected in mobile ads. That's not supposed to happen

A library patron reported seeing mobile ads that appeared to mirror her audiobook borrowing, prompting an investigation into whether library apps (OverDrive/Libby, Baker & Taylor Boundless) or the San Francisco Public Library’s website tracking enabled remarketing. Security analysis suggested Libby was largely free of third‑party tracking, while Boundless’ ecosystem and SFPL’s primary site employed trackers and pixels that could theoretically support targeted ads, though no definitive data-sharing path was confirmed. The piece highlights the tension between library privacy ethics and ad-tech practices, emphasizing the opacity of ad targeting and gaps in privacy protections and disclosures.