diff --git a/include/mfapi.h b/include/mfapi.h
index 346bd38d924..43f5cd60877 100644
--- a/include/mfapi.h
+++ b/include/mfapi.h
@@ -380,6 +380,14 @@ typedef enum
     MF_TOPOSTATUS_ENDED = 400,
 } MF_TOPOSTATUS;
 
+/* Media Session capabilities. */
+#define MFSESSIONCAP_START                 0x00000001
+#define MFSESSIONCAP_SEEK                  0x00000002
+#define MFSESSIONCAP_PAUSE                 0x00000004
+#define MFSESSIONCAP_RATE_FORWARD          0x00000010
+#define MFSESSIONCAP_RATE_REVERSE          0x00000020
+#define MFSESSIONCAP_DOES_NOT_USE_NETWORK  0x00000040
+
 HRESULT WINAPI MFAddPeriodicCallback(MFPERIODICCALLBACK callback, IUnknown *context, DWORD *key);
 HRESULT WINAPI MFAllocateWorkQueue(DWORD *queue);
 HRESULT WINAPI MFAllocateWorkQueueEx(MFASYNC_WORKQUEUE_TYPE queue_type, DWORD *queue);