diff --git a/src/gainmap.c b/src/gainmap.c
index e1c84badfc..6801b5ebe2 100644
--- a/src/gainmap.c
+++ b/src/gainmap.c
@@ -286,7 +286,7 @@ avifResult avifImageApplyGainMap(const avifImage * baseImage,
 {
     avifDiagnosticsClearError(diag);
 
-    if (baseImage->icc.size > 0) {
+    if (baseImage->icc.size > 0 || gainMap->altICC.size > 0) {
         avifDiagnosticsPrintf(diag, "Tone mapping for images with ICC profiles is not supported");
         return AVIF_RESULT_NOT_IMPLEMENTED;
     }