Kant lectured on natural law twelve times, and appears to have always used Gottfried Achenwall’s Jus naturae in usum auditorium, 5th ed [Göttingen 1763]. Only two sets of notes are known to us, and of these only Feyerabend is available. See the Natural Law lectures.
Naturrecht Feyerabend [Lehmann 1979].
Bound, quarto volume (17 x 21 cm), 116 pp. On the title-page: “Kants Naturrecht / gelesen / im / Winterhalben Jahre 1784.” At the bottom right: “Gottfr: Feyerabend.” Both sheets and pages are numbered (the former by a librarian, the latter perhaps by the copyist). Very neatly written, ornate headings, margins about one-sixth the page width. Catchwords used throughout. Some marginalia (possibly written in a second hand), appears to be inserted into the text (although on ms 49 it is clearly the same hand).
A “Godfried Feyerabend” of Neidenburg, Prussia, matriculated at the university on 6 May 1783 [Erler 1911, ii.576].
This is part of the Mrongovius Nachlass in Gdansk/Danzig [Günther 1909, 214 (see entry)]. Natorp [AA 6:529] and Horn  examined this manuscript in Danzig, and included a brief section on “De Matrimonio”. Horn’s transcription is an improvement on that found in the Academy edition [AA 27: 1378-80].
Kant lectured on the two-volume text by Gottfried Achenwall: Jus naturae in usum auditorum, pars posterior, Books 2-4, 5th ed. (Göttingen: Victor Bossiegel, 1763. Scholars have had access to Kant's copy of only the 2nd volume, the annotations to which were published in the Academy edition (AA 19:325-613) before that volume was lost during World War II. Because the bulk of the Feyerabend notes concern the first volume of Achenwall, Kant’s many reflections preserved from his copy of the second volume usefully supplement the lecture notes [Delfosse, et al, 2014a, xi].
Apart from being our only available notes from Kant’s lectures on natural law, they are of particular interest because Kant was composing his Groundwork of the Metaphysics of Morals [writings] at the time and the notes provide many helpful insights into that text; cf. Delfosse, et al [2010, ix-xi], and the list of parallel texts [xl-xli].
 The matriculation book entry reads: “Feyerabend Godfr., Neidenburg. Boruss.” The former Neidenburg, Prussia (now: Nidzica, Poland), lies about 170 km due south of Königsberg/Kaliningrad.
(1) Ms: Gdansk/Poland, Biblioteka PAN [Ms. 2215].
(2) Film: Marburg Kant-Archiv [Film 4].
(1) Horn [1936, 51-52]. This is a brief selection, covering the section “De Matrimonio” [ms. 111-12].
(2) Lehmann [1979; AA 27:1319-94]. This transcription is not wholly reliable, and should be checked against the manuscript.
(3) Bordoni . Translation into Italian of the introductory section of the lectures (AA 27:???-???, as published by Lehmann ??).
(4) Delfosse, et al. [2010, 3-15]. Transcription of the introductory section of the lectures, corresponding to the text transcribed by Lehmann at AA 27:1317-29.
(5) Costa Mattos . Translation into Portuguese of the introductory section of the lectures (AA 27:???-???, as published by Lehmann ??).
(6) Delfosse, et al. [2014a, xxvii-xcvii]. Transcription of latter part of the lectures, corresponding to the text transcribed by Lehmann at AA 27:1329-94.
(7) Hinski/Bordoni . Translation into Italian of the Feyerabend notes as transcribed in Delfosse, et al. [2010, 2014a].
(8) Marey/Madrid . Translation into Spanish of the introductory section of the Feyerabend notes as transcribed in Delfosse, et al. .
(9) Rauscher . Translation into English of the Feyerabend notes as transcribed in Delfosse, et al. [2010, 2014a].
Listed in Stargardt’s auction catalog (#234, item 158) as: “Fr. von Gentz, Collegienheft über Kants Rechtslehre (Königsberg 1784) 28 p. folio” [pdf]. This auction of materials rrom the collection of Zeune-Spitta was held on November 23-25, 1908.
Friedrich von Gentz (1763-1832) matriculated at the Albertina on 26 April 1783 to study law, having first studied at Frankfurt/Oder. His father was the Director of the Mint in Berlin, and the son made a name for himself as a conservative intellectual. See Gentz’ letter to Kant (16 April 1783 [AA 10:314, #192]) and Kant’s letter to Mendelssohn (16 August 1783 [AA 10:344-47, #206]), as well as Gause [1996, ii.255-56; 1974, 27-28] and the long entry in the ADB [viii.577-93].
(1) Ms: private possession. Lost.