Reddit this week filed suit against Perplexity and three other companies — Oxylabs UAB, AWM Proxy, and Serp Api — for allegedly engaging in so-called AI scraping without authorization. According to the lawsuit, filed in federal court in New York, the four companies collected millions of posts on Reddit with the aim of monetizing them.

Scrapers bypass technical protections to steal data that can then be sold to clients who want the material for AI training. Reddit is a prime target because it is one of the largest and most dynamic collections of human conversation ever created, Reddit’s chief legal officer Ben Lee said in a statement cited by the AP.

In June, Reddit filed a similar lawsuit against Anthropic, another AI company accused of collecting data without authorization. And last year, it demanded money from Microsoft for material it said the company had used for training purposes.