Peer Review Under Fire
One in Five ICLR 2026 Reviews Fully AI-Generated, Analysis Finds
Pangram Labs scanned all 75,800 submitted reviews and detected ∼21% as fully machine-written — with hallucinated citations as a tell. The finding lands as the ML community grapples with whether its flagship conference can still reliably peer-review the research it produces.
The International Conference on Learning Representations confronted a crisis of self-referential irony this week: the flagship venue where AI research is certified as credible may itself have been reviewed substantially by AI. Pangram Labs, a text-provenance startup, analyzed every one of the 75,800 reviews submitted for ICLR 2026 and estimated that roughly 21% — approximately 15,900 reviews — were fully AI-generated. More than 50% of all reviews showed detectable AI involvement at some level.
The investigation was sparked by CMU professor Graham Neubig, who posted on social media about suspicious feedback he received on a paper submission: the review was grammatically flawless yet made specific claims about a paper section that did not exist in the submitted version — a classic hallucination signature. His post drew hundreds of responses from researchers who had observed similar anomalies.
Pangram’s methodology combined stylometric analysis, perplexity scoring, and structural fingerprinting. The firm noted that hallucinated citations — references that sound plausible but do not correspond to any published paper — appeared in a non-trivial share of the flagged reviews, a pattern that purely human reviewers would be extremely unlikely to produce. The company published its full methodology alongside the results, inviting peer scrutiny of its own detection pipeline.
The implications extend well beyond this year’s program committee. ICLR 2026 received record submissions; the volume itself is widely acknowledged to have outpaced the community’s capacity for careful human review. Program chairs now face pressure to retroactively audit decisions, clarify policies for future rounds, and potentially introduce verified-human review requirements — all while the community’s trust in published conference results is materially in question. The findings reignite a debate that surfaced after NeurIPS 2024, when a controlled experiment showed reviewers could not reliably distinguish AI from human reviews, but this marks the first large-scale empirical measurement at a major venue.