Study of a Million Posts Finds Roughly a Quarter of Longform Social Content Is Fully AI-Written, Led by LinkedIn

A new analysis of more than one million social media posts concludes that AI-generated text has become pervasive across major platforms, with LinkedIn accounting for the largest share of machine-written content and nearly a quarter of all longform posts flagged as fully AI-generated. The findings, published July 9, 2026 by AI-detection company Pangram Labs, offer one of the first large-scale attempts to quantify how much of what people read in their feeds is written by software rather than humans.