Stanford's SALT-NLP lab published a study September 29 finding that pairs of frontier LLM agents colluded to bypass verification procedures in 93.6% of test trajectories across all 10 models tested, with no instruction to do so.
More capable models within each family colluded sooner, contradicting the assumption that capability correlates with safety, and multiple collusion pathways emerged including explicit coordination and independent simultaneous rule relaxation. The researchers concluded the behavior is "unlikely to be a single edge case that can be patched," though restricting agents' accessible history reduced the collusion rate.