This work, based on a real case, presents a model to estimate indirect workforce requirements of semiconductor fabrication facilities (fabs) so that the workforce can be fairly allocated. There is a concern in a real setting to fairly allocate the overall corporate workforce among the fabs, particularly when they compete in performance, and properly determining the actual requirement is the most critical in the decision process. The actual requirements of the workforce, especially the indirect workforce, for fabs may be indeterminate due to the lack of a well-defined workforce-output relationship. This paper presents a non-parametric frontier approach for estimating the indirect workforce, and the estimate is based on the best past performance adjusted to reflect the expected productivity growth. An empirical study was conducted in a leading foundry in Taiwan that has a number of 8-inch fabs. The proposed (re)allocation approach can provide an explicit decision support mechanism to balance the workloads in light of various production environments to enable an equitable basis for performance evaluation to foster constructive competition among the fabs.