This dissertation analyzes a key icon within the history of artists’ struggles for equity, and within the rich intersection of art and law: The Artist’s Reserved Rights Transfer and Sale Agreement, written by conceptual art curator Seth Siegelaub with attorney Robert Projansky in New York in 1971. Widely known among artists as the Artist’s Contract, this enduringly controversial legal agreement was devised to “remedy inequities” in the field by securing ongoing economic and property rights for artists in their sold works. By asserting that art was “no ordinary chattel,” the Artist’s Contract called on collectors and museums to reflect critically on the ways in which they use art as property (e.g., for speculation, for status), and attend to the welfare of the artist and to the artist’s agency. It also acknowledged the economic interdependence of artist and collector, and more so, aimed to reposition that bond as one of interpersonal trust. In doing so, it challenged market and legal standards, sparking key debates: Who owns artworks–producers or purchasers? What responsibilities does ownership entail? Whose “rights” count, and who decides? My extensive archival research in art and legal history sources, and interviews with artists, dealers, legislators, and attorneys revealed the origins of the Contract in conceptual art practices, the anti-war, civil rights, and feminist movements, influence from professionals in finance and law, European concepts of artists’ rights, as well as new art market regulations. Though never widely used, the Artist’s Contract remains frequently cited and reproduced by art and legal scholars as a model for how property and contractual relations might be reconfigured along alternate principles of reciprocity, in art and beyond. The dissertation’s introduction examines the growing subfield of Art and Legal Studies while positioning the Artist’s Contract as a social artifact of a period of abundant activism, art market growth, and a changing legal discourse interested more in “law in action” than “law on the books.” Chapter 1 examines the activities of Seth Siegelaub from 1964–69 as a young dealer and organizer of conceptual art exhibitions. In these years he introduced radical new models for the circulation of art while also orchestrating complex patronage relationships behind the scenes. I illuminate Siegelaub’s experiments with art gallery business models, and his relationships with patrons who were professionals in finance and law as key influences behind the Contract. Chapter 2 examines the practices of the artists with whom Siegelaub most closely collaborated from 1967–70: Robert Barry, Douglas Huebler, Joseph Kosuth, and Lawrence Weiner. Here I foreground the ways in which each artist experimented with alternate models of ownership through terms accompanying their works. I argue that this experimentation—present among peer artists as well—was another strand of influence behind the Contract. In Chapter 3 I examine the rhetoric and platforms of artists’ advocating for greater rights in their work in 1969–70, as well as changes in legislation through the later 1960s regulating the art market and granting artists increased rights in their work. These movements further informed the Contract. Chapter 4 traces the actual writing of the Contract as recorded in Siegelaub’s dense notes documenting the process. Here I uncover overlooked but important voices that molded its terms, repositioning the Contract as an amalgamation of various art world constituencies: art dealers, attorneys, artists, curators, accountants, and more. In doing so, I argue that the contradictions within the Contract render it less a “failed” project–as previous art historians have concluded–than an encapsulation of these figures’ varying interests and views. Here, the Contract no longer appears to deliver any singular notion of property rights, but instead is designed to elevate the relational dimensions of agreements, and to be a tool for articulating that relationality. Chapter 5 examines the early circulation and uses of the Contract until 1972, when Siegelaub ceased participating in art and relocated outside Paris. Here I examine the ways in which artists such as Hans Haacke and Carl Andre employed the Contract as a means of critiquing the art market. I also examine other artists who were not able to use it due to power imbalances and discrimination, and I uncover the relevance of the Contract to feminist activists like Lucy R. Lippard and the Los Angeles Council of Women Artists. In these latter examples, and in more contemporary uptakes of the Artist’s Contract, its vision of equity reaches beyond economic and property rights to principles of representation and repair. Such reinterpretations of this radical document from fifty years ago render its influence today worthy of closer investigation.