Despite considerable research suggesting that creators value attribution -- that is, being named as the creator of a work -- U.S. intellectual property (IP) law does not provide a right to attribution to the vast majority of creators. On the other side of the Atlantic, however, many European countries give creators, at least in their copyright laws, much stronger rights to attribution. At first blush it may seem that the U.S. has gotten it wrong, and the Europeans have made a better policy choice in providing to creators a right that they value. But for reasons we will explain in this Article, matters are much more complicated.This Article reports a series of experiments that are the first to attempt to measure quantitatively the value of attribution to creators. In previous research, we have shown that creators of IP are subject to a that results in their assigning substantially higher value to their works than neoclassical economic theory predicts. The first two experiments reported in this Article suggest a way that the creativity effect may be reduced: creators are willing to sacrifice significant economic payments in favor of receiving attribution for their work. The value to creators of attribution raises the question whether U.S. IP law should be restructured to provide attribution as a creator's default right.The third and most important experiment reported here casts doubt on the value of giving creators such a default right, because creators value attribution differently depending on whether the legal rule gives it to them as an initial entitlement or not. When creators are given a right to attribution as a default, they value credit four times higher than when attribution is not the default option. Our findings make clear that creators value attribution, and that the prospect of obtaining it can lead to a more efficient level of transacting. At the same time, paradoxically, our findings suggest that we should exercise caution before we restructure U.S. law, which provides no right to attribution for the vast majority of creators. Indeed, it is possible, under conditions that we will describe, that providing creators with a default right to attribution will result in less efficient transacting.Finally, our findings have implications for property theory which are broader than IP law or attribution rights. Our third experiment suggests that a party who enjoys a default legal right as part of her initial complement of rights will tend to treat that legal right in a fashion similar to any other form of initial entitlement, and overvalue it relative to what neoclassical theory would predict. This suggests a principle regarding how to efficiently structure default rules in any setting. All other factors being equal, an efficiently structured default rule will locate the initial legal entitlement in the party who is either less likely to overvalue the entitlement, or, if overvaluation seems inevitable regardless of where the initial entitlement is placed, is likely to overvalue it less.INTRODUCTIONImagine that you are a young and as yet unknown author. You have been contacted by a publishing company that wants you to assist a famous politician in writing her memoirs. The company gives you a choice between two contracts: the first will pay you $25,000 but your name will not appear anywhere on the book, while the second will pay you $10,000 but your name will appear as a second author on the book's cover and title page. If you are like most people, you are certainly attracted to the extra cash. But credit is probably also worth something to you as well. You may value being named as an author because you feel it is morally right that you get credit, or because it will enhance your reputation and social standing, or because it could help you receive other, more lucrative writing contracts in the future. Would you be willing to take the smaller payment in exchange for having your name on the book? …