19 Teves - R' Aryeh Leib ben R' Yosef HaKohen Heller (1813) author of Ketzos Hachoshen, Avnei Miluim and Shev Shmaitsa. All very famous seforim on halacha.
19 Teves - R' Avrohom Shmuel Binyamin Sofer (1871) oldest son of R' Moshe, the Chasam Sofer
19 Teves - R' Menachem Mendel Zaks (1974), son-in-law of the Chofetz Chaim
20 Teves - R' Moshe ben R' Maimon (1204) the Rambam
20 Teves - R' Yaakov ben R' Masoud Abuchatzeira (1880) Great mekubal and the grandfather of Baba Sali
21 Teves - R' Yisroel Dov Ber ben R' Yosef of Vilednik (1850), author of Shearis Yisroel, great tzadik and miracle worker, primary talimid of R' Mottel of Chernobyl, his kever in Vilendnik, Ukraine gets many visitors.
21 Teves - Rav Matzliach Mazuz of Djerba HY"D, author of Ish Matzliach (1971)
21 Teves - R' Yitzchok ben R' Abba Abuchatzeira (1991) Great-grandson of R' Yaakov Abuchatzeira
22 Teves - R' Sholom ben R' Mordechai Yosef Moshe Moskovitz, the Shotzer Rebbe of
22 Teves - R' Shmuel Heller, Rav of Tzefas (1884)
22 Teves - R' Yehuda Leib ben R' Shlomo Eiger of Lublin (1888) grandsonof R' Akiva Eiger, talmid of the Kotzker and Izhbitza, author of Toras Emes and Imrei Emes
22 Teves - R' Avrohom Elchonon ben R' Dovid Shlomo Spector (1973) descendant of the Chozeh. Breslover Tzadik who knew the whole Shas, Medrash, Zohar and more by heart.
23 Teves - R' Refoel Yitzchok Zerachia Azulai (1765) father of the Chida
23 Teves - R' Mordechai Gifter (1991), Rosh Yeshiva of Telz
24 Teves - R' Naftali ben R' Yitzchok Hakohen Katz (1719, some have the date as 26 Teves), author of Semichas Chachomim and Rov of Ostraha and Frankfurt-on-Main. He is buried in Istanbul, where he died, en route to Eretz Yisroel. He was a descendant of the Maharal of Prague. R' Nachman of Breslov was one of his descendants
24 Teves - R' Shneur Zalman ben R' Boruch of Liadi (1813), first Lubavitcher Rebbe, author of the Tanya and Shulchan Aruch Harav
24 Teves - R' Shmuel Borenstein of Sochatchov (1926), the Shem MiShmuel son of ben R' Avrohom, the Avnei Nezer
24 Teves - R' Avraham Shmuel Binyamin ben R' MosheSofer, author of the Teshuvos Divrei Sofer (1948) descendant of the Chasam Sofer
24 Teves - R' Moshe Mordechai ben R' Shimon Noson Nota Biderman of Lelov (1987) Great tzadik from a family that was in Yerushalayim since 1850.
24 Teves - R' Yosef of Yampola (1812 some have the date as 20 Shvat) ben R' Yechiel Mechel of Zlotchov24 Teves - R' Meir ben R' Yehuda Leib Greenwald (1852) Maharam Ash
25 Teves - R' Moshe Tzvi ben R' Shimon Shlomo Giterman of Savran (1837) was a talmid of R' Levi Yitzchok of Berditchev and R' Boruch of Mezibuz. He was a fierce opponent of R' Noson of Breslov, though interestingly his son, R' Shimon Shlomo was on good terms with the Breslover Chassidim.
25 Teves - Rav Eliyahu Eliezer ben R' Reuven Dov Dessler (1954), author of Michtav M'Eliyahu and Mashgiach in
25 Teves - Rav Moshe Tikochinsky, Mashgiach of Slabodka