In Wired, James Daily analyzes the contract between Bilbo Baggins and Thorin’s company:
Ordinarily I don’t discuss legal issues relating to fictional settings that are dramatically different from the real world in terms of their legal system. Thus, Star Wars, Star Trek, Tolkien’s Middle Earth, etc. are usually off-limits because we can’t meaningfully apply real-world law to them. But the contract featured in The Hobbit: An Unexpected Journey was just too good a topic to pass up, especially since you can buy a high-quality replica of it that is over 5 feet long unfolded.
First, it seems fairly clear (to me, anyway) that Tolkien wrote the Shire (where hobbits live) as a close analog to pastoral England, with its similar legal and political structures. For example, the Shire has a mayor and sheriffs, and there is a system of inheritance similar to the common law. The common law fundamentals of contract law have not changed significantly since the time that the Shire is meant to evoke, so it makes sense that the contract would be broadly similar to a modern contract (and likewise that we could apply modern contract law to it).
So, without further ado, let’s get to it.