Tools to identify controlled pathogen or toxin DNA sequences are crucial for biosecurity. Testing the efficacy of such tools is a complex challenge, however, and there are currently no shared materials or methods that can help support such testing. To address this gap, we convened stakeholders for a Workshop on Testing Sequence Screening on November 15th, 2022, to discuss how shared test resources might be developed. Discussion focused specifically on nucleic acid and amino acid sequences controlled by the Australia Group Common Control Lists, US Commerce Control List, the US Select Agents and Toxins List, and the EU Dual Use List. Key conclusions from this workshop are: There is general support in the stakeholder community for building shared test resources. Tests for controlled sequences have value, even if non-controlled sequences of concern are not covered. Multiple distinct classes of test have value, including: tests at different levels of comprehensiveness directed at controlled sequences, tests for accurate classification of non-threat sequences, including non-threat portions of threat organism genomes, and tests directed at specific evasion techniques. Information hazards need to be managed and mitigated (particularly those related to evasion algorithms and to potential biorisk sequences in non-listed pathogens), but the test resources should be made as public as possible to enable input from a broad range of communities. High-quality annotations and metadata are valuable but expensive, so there is also value in using poorly annotated sequences to provide breadth (e.g. in variant coverage). Test resources will need ongoing maintenance, so their design needs to take sustainability and resource availability into account.