SpiceDB is a graph database purpose-built for storing and evaluating access control data. Use of a relation of the form: "relation folder: folder | folder#parent" with an arrow such as "folder->view" can cause LookupSubjects to only return the subjects found under subjects for either "folder" or "folder#parent". This bug only manifests if the same subject type is used multiple types in a relation, relationships exist for both subject types and an arrow is used over the relation. Any user making a negative authorization decision based on the results of a LookupSubjects request with version before v1.30.1 is affected. Version 1.30.1 contains a patch for the issue. As a workaround, avoid using LookupSubjects for negative authorization decisions and/or avoid using the broken schema.