diff --git a/Tests/test_lib_pack.py b/Tests/test_lib_pack.py
index 635b5679a..0b1a43880 100644
--- a/Tests/test_lib_pack.py
+++ b/Tests/test_lib_pack.py
@@ -151,10 +151,6 @@ class TestLibPack(PillowTestCase):
         self.assert_pack("YCbCr", "YCbCr", 3, (1, 2, 3), (4, 5, 6), (7, 8, 9))
         self.assert_pack("YCbCr", "YCbCr;L", 3,
                          (1, 4, 7), (2, 5, 8), (3, 6, 9))
-        self.assert_pack(
-            "YCbCr", "YCbCrX",
-            b'\x01\x02\x03\xff\x05\x06\x07\xff\t\n\x0b\xff',
-            (1, 2, 3), (5, 6, 7), (9, 10, 11))
         self.assert_pack(
             "YCbCr", "YCbCrK",
             b'\x01\x02\x03\xff\x05\x06\x07\xff\t\n\x0b\xff',
@@ -471,12 +467,6 @@ class TestLibUnpack(PillowTestCase):
             "YCbCr", "YCbCr;L", 3, (1, 4, 7), (2, 5, 8), (3, 6, 9))
         self.assert_unpack(
             "YCbCr", "YCbCrK", 4, (1, 2, 3), (5, 6, 7), (9, 10, 11))
-        self.assert_unpack(
-            "YCbCr", "YCbCrX", 4, (1, 2, 3), (5, 6, 7), (9, 10, 11))
-        self.assert_unpack(
-            "YCbCr", "YCbCrXX", 5, (1, 2, 3), (6, 7, 8), (11, 12, 13))
-        self.assert_unpack(
-            "YCbCr", "YCbCrXXX", 6, (1, 2, 3), (7, 8, 9), (13, 14, 15))
 
     def test_LAB(self):
         self.assert_unpack(
diff --git a/src/PIL/TiffImagePlugin.py b/src/PIL/TiffImagePlugin.py
index 977d1da14..fa8f984f4 100644
--- a/src/PIL/TiffImagePlugin.py
+++ b/src/PIL/TiffImagePlugin.py
@@ -258,14 +258,9 @@ OPEN_INFO = {
     (MM, 5, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0)): ("CMYK", "CMYKXX"),
 
     # JPEG compressed images handled by LibTiff and auto-converted to RGB
+    # Minimal Baseline TIFF requires YCbCr images to have 3 SamplesPerPixel
     (II, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
     (MM, 6, (1,), 1, (8, 8, 8), ()): ("RGB", "RGB"),
-    (II, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGB", "RGB"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8), (0,)): ("RGB", "RGB"),
-    (II, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGB", "RGB"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8, 8), (0, 0)): ("RGB", "RGB"),
-    (II, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGB", "RGB"),
-    (MM, 6, (1,), 1, (8, 8, 8, 8, 8, 8), (0, 0, 0)): ("RGB", "RGB"),
 
     (II, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),
     (MM, 8, (1,), 1, (8, 8, 8), ()): ("LAB", "LAB"),
diff --git a/src/libImaging/Pack.c b/src/libImaging/Pack.c
index 5c298c6c5..6d42d8491 100644
--- a/src/libImaging/Pack.c
+++ b/src/libImaging/Pack.c
@@ -608,7 +608,6 @@ static struct {
     /* video (YCbCr) */
     {"YCbCr",   "YCbCr",        24,     ImagingPackRGB},
     {"YCbCr",   "YCbCr;L",      24,     packRGBL},
-    {"YCbCr",   "YCbCrX",       32,     copy4},
     {"YCbCr",   "YCbCrK",       32,     copy4},
     {"YCbCr",   "Y",            8,      band0},
     {"YCbCr",   "Cb",           8,      band1},
diff --git a/src/libImaging/Unpack.c b/src/libImaging/Unpack.c
index 7bb8064ee..56be12e07 100644
--- a/src/libImaging/Unpack.c
+++ b/src/libImaging/Unpack.c
@@ -1428,9 +1428,6 @@ static struct {
     /* video (YCbCr) */
     {"YCbCr",   "YCbCr",        24,     ImagingUnpackRGB},
     {"YCbCr",   "YCbCr;L",      24,     unpackRGBL},
-    {"YCbCr",   "YCbCrX",       32,     copy4},
-    {"YCbCr",   "YCbCrXX",      40,     copy4skip1},
-    {"YCbCr",   "YCbCrXXX",     48,     copy4skip2},
     {"YCbCr",   "YCbCrK",       32,     copy4},
 
     /* LAB Color */