Haskamot (rabbinical approbations) to Hebrew books have an very interesting history. There are a few different forms of haskamot, perhaps the most important form is that which granted the author and/or publisher a copyright. Typically, the haskamah would prohibit republishing the particular book for a period of ten or fifteen years, etc. In some instances, it was not only the particular book but any book in the field. For example, the haskamah to R. Yom Tov Lipmann Heller's edition of the Mishna with his commentary, Tosefot Yom Tov (Prague 1617) provides that "it is prohibited from printing any Mishnayot with any commentary for four years."
The history of this particular form haskamah begins with the approbation that appears on the first Rabbinic bible (Venice 1517). As Jordan Penkower has previously provided, the approbation which appears at the end of Chronicles states that it is
forbidden [for] any one under the penalty of excommunication and also the loss of the books in the territories of the Holy Roman Church, to print or cause to be printed these books with the Targum or without the Targum and the Hebrew Commentaries of the Bible for the space of ten years from 1515.
This approbation is somewhat unique for Hebrew books as it was not given by a Rabbi but instead by Pope Leo X. Indeed, the version of this bible which contains this approbation was also dedicated to the Pope. Felix Pratensis, the editor and former Jew (he became a Augustin monk), explains in the dedication that the very idea of including the Targumim is favorable to the Church. He explains that
the text we have added the ancient Hebrew and Chaldee Shcola, to wit the common Targum and that of Jerusalem. These contain many obscure and recondite mysteries, not only useful, but necessary to the devout Christian. We have wished with good reason to publish the whole under the sanction of your name [Leo X], for whereas on this book the foundation and the entire superstructure of Christianity rests, you are revered by us as the chief head of the Christian Church on earth and no one can deny the appropriateness of the dedication to you of our work.
Another odd approbation appears in the book printed much later in Lemberg, 1878. This book, Peni Abraham, authored by R. Abraham Abba Seelenfreund includes approbations dated years before the book was ever published. For example, R. Meir Perles' approbation is dated 1852. But, that approbation is not unique in the history of approbations. In fact, the first Ashkenazik approbations, appearing in R. Shlomo Luria's Hakmat Shlomo (Krakow 1581) contains the approbation of R. Kalman of Worms dated 1542. Instead, the odd approbation is that of R. Yitzhak Meir Alter, the Gerrer Rebbi otherwise known as the Hiddushei ha-Rim. The reason this approbation is odd does have to do with the date. Specifically, it is dated, Rosh Hodesh Tamuz, 1870. The problem is that R. Alter died some four years earlier on the 23 of Adar 1866! Now it is possible that instead of 5630 (1870) it should read 5620 (1860) and the letter Chuf was inadvertently changed to a Lamed, but in all events, it is a rather interesting slip of the pen.
Now, it is not only the approbation that is of interest, in fact, R. Seelenfreund himself was somewhat of a character. According to the brief biography by R. Yekutiel Yehuda Greenwald, R. Seelenfreund ended up divorcing his first wife during sheva Berakhot. Additionally, although R. Seelenfreund was the Rabbi in Zaloshick (Poland) for a period of time, in 1875 he took a position in Kosice, Hungary for a short period of time. While R. Seelenfreund was considered Ultra-Orthodox, as the term was used by the Hungarians, Kosice, as were many cities in Hungry was split between three Jewish factions, Reform, Ultra-Orthodox and Status Quo. R. Seelenfreund was appointed Rabbi of the Status Quo synagogue and thought that his relationships with Ultra-Orthodox Rabbis would allow him to remain to be viewed as such. Indeed, on his first sefer, Pras Avot (Lemberg 1865), he obtained the approbation of R. Yosef Shaul Nathanson. It was R. Nathanson's suggestion for the title of the book to be Pras Avot. It appears that R. Seelenfreund, however, was very wrong in his calculation regarding Kosice. He eventually left Kosice and returned to Zaloshick but not before relationships between himself and the community broke down. He even published a small book, Kol Shover Shekarim (Kosice 1878) to defend himself. It is unclear why much of this history of R. Seelenfreund does not appear in Cohen's biography of R. Seelenfreund from Hakmei Hungaria. It appears that Cohen was unaware that R. Seelenfreund left Kosice or that he published Kol Shover Shekarim.
 For this and other similar approbations see Nahum Rakover, Copyright in Jewish Sources (Israel 1991), 150-53 (Hebrew). Both Rakover's work as well as Benayahu's, see infra n3, break new ground on the issue of approbations. The new edition of the Encyclopaedia Judaica, however, does not use any of these sources. In fact, the new version merely reprints the earlier article on haskma which appeared in the 1971 edition and is seriously lacking. This is but another example of how the new version has significant gaps. See Shnayer Z. Leiman's review of the new edition here and Shlomo Zalman Havlin's additional note on the topic here.
 The translation of this and the next quote is taken from Christian D. Ginsburg, Introduction to the Massoretico Critical Edition of the Hebrew Bible (Ktav Press 1966), 935-36, 946.
 In addition, Pratensis claims that this edition was unique as the prior editions "hav[e] almost as many errors as words in them" and that "no one has attempted [such an edition] before." Ginsburg in his discussion about this edition shows, however, that in fact previous editions were (close) to error free. Ginsburg bemoans the fact that "Felix Pratensis should have been betrayed to resort to such unfair expedients." But, it is possible that Pratensis' claim regarding the novelty of the work was necessary in part due approbations. Not Rabbinic approbations but the approbation of the Venetian Senate. This is so, as in 1517 the Senate passed a law that would abolish all printing monopolies (copyrights) and hence forth would only grant monopolies for works which "are new or which have never been printed before." Horatio Brown, The Venetian Printing Press (London 1891), 74. Indeed, Bomberg, the printer of this edition had appealed to the Senate for a monopoly when he began printing in 1515 and which the new law abolished. See Meir Benayahu, Copyright, Authorization & Imprimatour for Hebrew Books Printed in Venice (Israel 1971), 17 (Hebrew). Thus, it is possible that Pratensis claim of novelty was to argue implicitly that this book qualified for a monopoly even under the new law as it was a "new" book.
 Y.Y. Greenwald, "The Descendants of the Rema and their Influence in Hungary," Sinai 28 (1951): 85-87 (Hebrew).
 Y.Y. Kohen, Hakmei Hungaria (Israel 1997), 342.