Reviewer Networks and AI-Agent Collusion: Theory and an Exploratory Experiment
Suraj Kumar · Team Coalition Dynamics
Submitted to AI Collusion Research Sprint. Sprint projects are early-stage work by participants, not Apart Research publications.
We investigate how organizational structures shape opportunities for collusion among AI agents. Our formal model distinguishes mechanically possible unauthorized approvals from mutually beneficial coalitions, characterizing how coalition requirements differ between reciprocal reviewer pairs and a four-agent review cycle under explicit incentive assumptions.
We developed a reproducible four-agent software release simulation and conducted an exploratory matched comparison (224 model-call slots). Both organizational structures deployed all eight qualified releases, but none of the 24 releases lacking mandatory verification. Preliminary analysis of 266 agent messages found no explicit proposals to exchange unauthorized approvals, although communication patterns differed between the structures.
These findings do not establish a causal effect of organizational structure on collusion. Our contribution combines a mathematical framework for analyzing coalition opportunities with an experimental testbed for investigating how incentives, communication, and organizational design affect realized agent behavior.
Reviews
The strongest part of this paper is the distinction between having the authority to approve an improper release and having an incentive to exchange approval favors. The independent-approval example is also useful: a completed review cycle can look suspicious even when no agreement exists. That is an important consideration when designing collusion detectors.
I appreciate the care taken with the pilot results. The paper distinguishes technical failures from refusals, incomplete verification from hidden vulnerabilities, and preliminary message screening from completed human review. It also clearly acknowledges that the experiment does not establish a difference in collusion between the networks.
The main limitation is that the reviewer assignment never became decisive for deployment. No owner authorized an unqualified release, so both networks stopped those releases before reviewer approval could change the outcome. Successful qualified releases show that the workflow functions, but not that the experiment can elicit or detect approval bargaining.
A useful next step would be to test a range of delivery incentives and confirm that agents can negotiate legitimate reciprocal arrangements. The network comparison could then be repeated across independently sampled runs, with human message adjudication completed. This is a thoughtful theoretical framing and a useful feasibility pilot, but the behavioral question remains open.
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Cite this project
@misc{kumar2026reviewer,
title = {{Reviewer Networks and AI-Agent Collusion: Theory and an Exploratory Experiment}},
author = {Suraj Kumar},
year = {2026},
month = oct,
note = {Submitted to AI Collusion Research Sprint, an Apart Research Sprint},
howpublished = {\url{https://apartresearch.com/sprints/projects/reviewer-networks-and-aiagent-collusion-theory-and-an-exploratory-experiment-nscv}},
url = {https://apartresearch.com/sprints/projects/reviewer-networks-and-aiagent-collusion-theory-and-an-exploratory-experiment-nscv}
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