diff --git a/doc/APIchanges b/doc/APIchanges
index 1939b8758f..d132dfab81 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2024-03-07
 
 API changes, most recent first:
 
+2024-10-xx - xxxxxxxxxx - lavu 59.41.100 - log.h
+  Add AVClass.state_flags_offset and AV_CLASS_STATE_INITIALIZED.
+
 2024-09-30 - xxxxxxxxxx - lavf 61.9.100 - avformat.h
   Add {nb_}coded_side_data to AVStreamGroupTileGrid.
 
diff --git a/libavutil/log.h b/libavutil/log.h
index 2860d4f039..4c8c92266f 100644
--- a/libavutil/log.h
+++ b/libavutil/log.h
@@ -46,6 +46,15 @@ typedef enum {
     AV_CLASS_CATEGORY_NB  ///< not part of ABI/API
 }AVClassCategory;
 
+enum AVClassStateFlags {
+    /**
+     * Object initialization has finished and it is now in the 'runtime' stage.
+     * This affects e.g. what options can be set on the object (only
+     * AV_OPT_FLAG_RUNTIME_PARAM options can be set on initialized objects).
+     */
+    AV_CLASS_STATE_INITIALIZED         = (1 << 0),
+};
+
 #define AV_IS_INPUT_DEVICE(category) \
     (((category) == AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT) || \
      ((category) == AV_CLASS_CATEGORY_DEVICE_AUDIO_INPUT) || \
@@ -155,6 +164,15 @@ typedef struct AVClass {
      *       instance of this class.
      */
     const struct AVClass* (*child_class_iterate)(void **iter);
+
+    /**
+     * When non-zero, offset in the object to an unsigned int holding object
+     * state flags, a combination of AVClassStateFlags values. The flags are
+     * updated by the object to signal its state to the generic code.
+     *
+     * Added in version 59.41.100.
+     */
+    int state_flags_offset;
 } AVClass;
 
 /**
diff --git a/libavutil/opt.c b/libavutil/opt.c
index b32a9432df..7dc4fdb062 100644
--- a/libavutil/opt.c
+++ b/libavutil/opt.c
@@ -185,6 +185,39 @@ static int opt_set_init(void *obj, const char *name, int search_flags,
         return AVERROR(EINVAL);
     }
 
+    if (!(o->flags & AV_OPT_FLAG_RUNTIME_PARAM)) {
+        unsigned *state_flags = NULL;
+        const AVClass *class;
+
+        // try state flags first from the target (child), then from its parent
+        class = *(const AVClass**)tgt;
+        if (
+#if LIBAVUTIL_VERSION_MAJOR < 60
+            class->version >= AV_VERSION_INT(59, 41, 100) &&
+#endif
+            class->state_flags_offset)
+            state_flags = (unsigned*)((uint8_t*)tgt + class->state_flags_offset);
+
+        if (!state_flags && obj != tgt) {
+            class = *(const AVClass**)obj;
+            if (
+#if LIBAVUTIL_VERSION_MAJOR < 60
+                class->version >= AV_VERSION_INT(59, 41, 100) &&
+#endif
+                class->state_flags_offset)
+                state_flags = (unsigned*)((uint8_t*)obj + class->state_flags_offset);
+        }
+
+        if (state_flags && (*state_flags & AV_CLASS_STATE_INITIALIZED)) {
+            av_log(obj, AV_LOG_ERROR, "Option '%s' is not a runtime option and "
+                   "so cannot be set after the object has been initialized\n",
+                   o->name);
+#if LIBAVUTIL_VERSION_MAJOR >= 60
+            return AVERROR(EINVAL);
+#endif
+        }
+    }
+
     if (o->flags & AV_OPT_FLAG_DEPRECATED)
         av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n", name, o->help);
 
diff --git a/libavutil/version.h b/libavutil/version.h
index 69519cfd06..18f1d00145 100644
--- a/libavutil/version.h
+++ b/libavutil/version.h
@@ -79,7 +79,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  59
-#define LIBAVUTIL_VERSION_MINOR  40
+#define LIBAVUTIL_VERSION_MINOR  41
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \