They just sold out, I always heard it was to divide up assets after a death that started it.
Most of the names are still produced to this day.
http://www.whiskyportal.com/distill...1071&DistilleryName=Stitzel-Weller+Distillery
Here is another good link,
http://www.bourbonenthusiast.com/forum/viewtopic.php?f=17&t=1629
From link...
1966 - Stitzel-Weller unveil the "Pappy" Van Winkle Fitz Mist Award to honor the memory of the late "Pappy" Van Winkle (Bev. Media, July 1966, p. 90).
1972 - Stitzel-Weller is purchased by Norton-Simon Inc., who
make it part of Somerset Imports. (UD Archives,
991.m.32).
o - Stitzel-Weller name is changed to Old Fitzgerald to
honor their best selling brand. (UD Archives,
991.m.32).
1984 - Old Fitzgerald is purchased by DLC. (C Morris,
Glenmore, 15/11/91).
1986 - DLC joins with Guiness. (C Morris, Glenmore, 15/11/91).
1992 - Guiness changes name of Old Fitzgerald back to Stitzel-
Weller. (M Veach, 14/8/92).
o - The Shively Stitzel-Weller distillery is closed (M
Veach, 28/1/93).
Barney