diff --git a/src/PIL/TiffTags.py b/src/PIL/TiffTags.py
index 86adaa458..761aa3f6b 100644
--- a/src/PIL/TiffTags.py
+++ b/src/PIL/TiffTags.py
@@ -203,6 +203,11 @@ _tags_v2: dict[int, tuple[str, int, int] | tuple[str, int, int, dict[str, int]]]
     531: ("YCbCrPositioning", SHORT, 1),
     532: ("ReferenceBlackWhite", RATIONAL, 6),
     700: ("XMP", BYTE, 0),
+    # Four private SGI tags
+    32995: ("Matteing", SHORT, 1),
+    32996: ("DataType", SHORT, 0),
+    32997: ("ImageDepth", LONG, 1),
+    32998: ("TileDepth", LONG, 1),
     33432: ("Copyright", ASCII, 1),
     33723: ("IptcNaaInfo", UNDEFINED, 1),
     34377: ("PhotoshopInfo", BYTE, 0),