arXiv:2605.08586v3 Announce Type: replace Abstract: This position paper argues that computer science conferences should require tamper-evident, nonrepudiable attestations of experimental results. We name the underlying problem experiment nonrepudiation: a compliant protocol must bind the numbers in a paper to an actual executed computation in a way the author cannot later alter or deny. The current system relies on self-reported checklists, optional code sharing, and author-controlled logging. None of these mechanisms answer the question a reviewer cannot check: did the code the paper describes produce the numbers the paper reports? We define the problem formally, state the security properties any compliant protocol must satisfy, and describe a threat model that includes attacks current approaches do not prevent. We frame the mechanism that provides this property as a proof-of-compute layer, a general requirement that computed results be admitted as evidence only when accompanied by a verifiable record of the computation that produced them. To show that the problem is solvable, we built K-Veritas, the official reference implementation and public infrastructure for experiment nonrepudiation, written in Go, which produces signed reports without accessing training data. K-Veritas is in use today, with a public registry of sealed records; it is not final, and we intend to improve it through community collaboration. We call on conferences and the community to treat nonrepudiation as a major requirement and to help build an open, independent standard for it.