Using software often means you have to sign a contract as a condition for using the software. This "end user license agreement," called a EULA, will lay out the terms under which the software can be used. For example, the EULA you sign to play a video game might say: "The player of this video game cannot cheat while playing the game." What if you breach the EULA by playing the game using a commercially available cheating "bot"? Is this copyright infringement? Or is this just a breach of contract? This may seem obscure, but the question matters a lot. For one thing, in this example, if the video game publisher has a copyright claim against the cheater, not just a contract claim, this could mean very large statutory damages versus no damages at all.
This is just one of many scenarios in which copyright owners use contracts to control the conditions of use, and whose breach may, or may not, give rise to copyright infringement. In his new article, Against Copyright Customization, Guy Rub addresses this thorny question—copyright or contract?—along with many closely related questions. For example: when is a software user a mere licensee versus an owner? (Spoiler alert: almost always!) The article is forthcoming in Iowa Law Review and a draft can be downloaded on SSRN.
I interviewed Guy about the article. Here is a transcription.