While the tax rate measures a firm’s incentive regarding where to earn income, we also need to detm hich kinds of firms are best able to manage their operations in a way that mitigates taxes and thus results in trapped foreign cash.Anecdotally,there is evidence that the effect is particularly pronounced in firms with high levels of intellectual property. Since such firms can move earnings from high-tax to low-tax jurisdictions using advantageous intra company transfer pricing(or income shifting), we would expect significant sales from one subsidiary to another, relative to total sales, to be indicative of this type of international tax planning. We construct a measure (related sales) that is the percentage of the firm’s total revenue that is derived from sales of its foreign subsidiaries, either to the parent or to its other foreign subsidiaries. We hypothesize that the tax effect should be greatest among those firms that are particularly adept at using related sales to move income across various tax jurisdictions.