While there were many restrictions on the bookseller, the job did have its benefits. The bookseller was free to produce and sell books, illuminate, or write for anyone they pleased like the Court, cathedral, or the wealthy laymen of the capital and provinces so long as they met their obligations to the university to which they had sworn oaths. In fact, most of their trade fell outside of the university regulation. There is an important distinction between the regulation of how books were traded within the university and how the booksellers were able to charge whatever the open market would bear. To the non-student or masters, there were no such restrictions on the booksellers. Between 1300–1500, the position of libraire was a closed position only open upon the resignation or death of a previous one. Aside from cheap books, it was only the libraire who was allowed to sell books in Paris. The university essentially guaranteed a monopoly on the sale of books for booksellers.