Four specific case studies are highlighted in Figure , each where the main task is Suzuki B1 and the auxiliary training task is one dataset from each of Suzuki R1-4. In each case study, a conventional single-task Bayesian optimization (STBO) benchmark for the Suzuki B1 reaction serves as a comparison. For each MTBO study, 96 datapoints from the auxiliary task were utilized. The average best yield for each algorithm is shown with a 95 % confidence interval over 20 repeated runs.