Chartularium universitatis Parisiensis, I, 532-34.
The university of masters and students at Paris as a perpetual reminder. Since that field is known to bring forth rich fruit, for which the care of the farmer colonus provides painstakingly in all respects, lest we, laboring in the field of the Lord to bring forth fruit a hundredfold in virtues and science, the Lord disposing, should be molested or impeded, especially by those who by a bad custom hang about the university of Paris for the sake of gain, which they make in mercenary works and assistance, we ordain by decree and decree by ordinance that the stationers who vulgarly are called booksellers (librarii), shall each year or every second year or whenever they shall be required by the university, give personal oath that, in receiving books to sell, storing, showing, and selling the same and in their other functions in connection with the university, they will conduct themselves faithfully and legitimately.
Also, since some of the aforesaid booksellers, given to insatiable cupidity, are in a way ungrateful and burdensome to the university itself, when they put obstacles in the way of procuring books whose use is essential to the students and by buying too cheaply and selling too dearly and thinking up other frauds make the same books too costly, although as those who hold an office of trust they ought to act openly and in good faith in this matter, which they would better observe if they would not simultaneously act as buyer and seller, we have decreed that the same booksellers swear, as has been stated above, that within a month from the day on which they receive books to sell they will neither make nor pretend any contract concerning those books to keep them for themselves, nor will they suppress or conceal them in order later to buy or retain them, but in good faith, immediately they have received the books or other things, they will offer them for sale at an opportune place and time. And if they shall be asked by the sellers, they shall estimate and state in good faith at how much they really believe the books offered for sale can be sold at a just and legitimate price, and they shall also put the price of the book and the name of the seller somewhere on the book so that it can be seen by one looking at it. They shall also swear that, when they sell the books, they will not assign or transfer them entirely to the purchasers nor receive the price for them until they have communicated to the seller or his representative what price he is going to receive, and that concerning the price offered for the book they will tell the pure and simple truth without fraud and deceit, nor otherwise in any way shall they attempt anything about their office by cupidity or fraud, whence any detriment could come to the university or the students.
Also, while the laborer is worthy of his hire, which too he licitly seeks by civil law (Proxenetica), since nevertheless the standard which should be maintained in such matters is frequently exceeded by the booksellers, we have decreed that the stationers swear that they will not demand for books sold beyond four pence in the pound and a smaller quantity pro rata as their commission, and these they shall demand not from the seller but the purchaser.
Also, since many damages come from corrupt and faulty exemplars, we have decreed that the said booksellers swear that they will apply care and pains with all diligence and toil to have true and correct exemplars.