diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM
index e594e3812..c3e8e1594 100644
--- a/WHATS_NEW_DM
+++ b/WHATS_NEW_DM
@@ -1,5 +1,6 @@
 Version 1.02.73 - 
 ====================================
+  Drop unsupported TRIM message for thin pool.
   Improve logging for fifo startup in dmeventd.
   Add few pointer validation in dmsetup.
   Support dm_task_get_driver_version() query without version string.
diff --git a/lib/metadata/thin_manip.c b/lib/metadata/thin_manip.c
index f66917c70..0c00e7a6a 100644
--- a/lib/metadata/thin_manip.c
+++ b/lib/metadata/thin_manip.c
@@ -70,7 +70,6 @@ int detach_pool_lv(struct lv_segment *seg)
 		switch (tmsg->type) {
 		case DM_THIN_MESSAGE_CREATE_SNAP:
 		case DM_THIN_MESSAGE_CREATE_THIN:
-		case DM_THIN_MESSAGE_TRIM:
 			if (tmsg->u.lv == seg->lv) {
 				log_debug("Discarding message for LV %s.",
 					  tmsg->u.lv->name);
@@ -151,7 +150,6 @@ int attach_pool_message(struct lv_segment *pool_seg, dm_thin_message_t type,
 	switch (type) {
 	case DM_THIN_MESSAGE_CREATE_SNAP:
 	case DM_THIN_MESSAGE_CREATE_THIN:
-	case DM_THIN_MESSAGE_TRIM:
 		tmsg->u.lv = lv;
 		break;
 	case DM_THIN_MESSAGE_DELETE:
@@ -173,7 +171,6 @@ int attach_pool_message(struct lv_segment *pool_seg, dm_thin_message_t type,
 	log_debug("Added %s message",
 		  (type == DM_THIN_MESSAGE_CREATE_SNAP ||
 		   type == DM_THIN_MESSAGE_CREATE_THIN) ? "create" :
-		  (type == DM_THIN_MESSAGE_TRIM) ? "trim" :
 		  (type == DM_THIN_MESSAGE_DELETE) ? "delete" : "unknown");
 
 	return 1;
@@ -200,7 +197,6 @@ int pool_has_message(const struct lv_segment *seg,
 		switch (tmsg->type) {
 		case DM_THIN_MESSAGE_CREATE_SNAP:
 		case DM_THIN_MESSAGE_CREATE_THIN:
-		case DM_THIN_MESSAGE_TRIM:
 			if (tmsg->u.lv == lv)
 				return 1;
 			break;
diff --git a/lib/thin/thin.c b/lib/thin/thin.c
index 65b130b8e..c04577371 100644
--- a/lib/thin/thin.c
+++ b/lib/thin/thin.c
@@ -62,15 +62,6 @@ static int _thin_pool_add_message(struct lv_segment *seg,
 		type = DM_THIN_MESSAGE_CREATE_THIN;
 	}
 
-	if (dm_config_get_str(sn, "trim", &lv_name)) {
-		if (lv)
-			return SEG_LOG_ERROR("Unsupported message format in");
-		if (!(lv = find_lv(seg->lv->vg, lv_name)))
-			return SEG_LOG_ERROR("Unknown LV %s for trim message in",
-					     lv_name);
-		type = DM_THIN_MESSAGE_TRIM;
-	}
-
 	if (!dm_config_get_uint32(sn, "delete", &delete_id)) {
 		if (!lv)
 			return SEG_LOG_ERROR("Unknown message in");
@@ -169,7 +160,6 @@ static int _thin_pool_text_export(const struct lv_segment *seg, struct formatter
 		switch (tmsg->type) {
 		case DM_THIN_MESSAGE_CREATE_SNAP:
 		case DM_THIN_MESSAGE_CREATE_THIN:
-		case DM_THIN_MESSAGE_TRIM:
 			if (!lv_is_thin_volume(tmsg->u.lv)) {
 				log_error(INTERNAL_ERROR
 					  "LV %s is not a thin volume.",
@@ -192,9 +182,6 @@ static int _thin_pool_text_export(const struct lv_segment *seg, struct formatter
 		case DM_THIN_MESSAGE_CREATE_THIN:
 			outf(f, "create = \"%s\"", tmsg->u.lv->name);
 			break;
-		case DM_THIN_MESSAGE_TRIM:
-			outf(f, "trim = \"%s\"", tmsg->u.lv->name);
-			break;
 		case DM_THIN_MESSAGE_DELETE:
 			outf(f, "delete = %d", tmsg->u.delete_id);
 			break;
@@ -302,10 +289,6 @@ static int _thin_pool_add_target_line(struct dev_manager *dm,
 								lmsg->u.delete_id, 0))
 				return_0;
 			break;
-		case DM_THIN_MESSAGE_TRIM:
-			/* FIXME: to be implemented */
-			log_error("Sorry TRIM is not yet supported.");
-			return 0;
 		default:
 			log_error(INTERNAL_ERROR "Unsupported message.");
 			return 0;
diff --git a/libdm/libdevmapper.h b/libdm/libdevmapper.h
index ce8b2bb16..dfbadaa27 100644
--- a/libdm/libdevmapper.h
+++ b/libdm/libdevmapper.h
@@ -650,7 +650,6 @@ typedef enum {
 	DM_THIN_MESSAGE_CREATE_THIN,		/* device_id */
 	DM_THIN_MESSAGE_DELETE,			/* device_id */
 	DM_THIN_MESSAGE_SET_TRANSACTION_ID,	/* current_id, new_id */
-	DM_THIN_MESSAGE_TRIM			/* device_id, new_size */
 } dm_thin_message_t;
 
 int dm_tree_node_add_thin_pool_message(struct dm_tree_node *node,
diff --git a/libdm/libdm-deptree.c b/libdm/libdm-deptree.c
index 061331630..e80db2fee 100644
--- a/libdm/libdm-deptree.c
+++ b/libdm/libdm-deptree.c
@@ -1404,11 +1404,6 @@ static int _thin_pool_node_message(struct dm_tree_node *dnode, struct thin_messa
 		r = dm_snprintf(buf, sizeof(buf), "delete %u",
 				m->u.m_delete.device_id);
 		break;
-	case DM_THIN_MESSAGE_TRIM:
-		r = dm_snprintf(buf, sizeof(buf), "trim %u %" PRIu64,
-				m->u.m_trim.device_id,
-				m->u.m_trim.new_size);
-		break;
 	case DM_THIN_MESSAGE_SET_TRANSACTION_ID:
 		r = dm_snprintf(buf, sizeof(buf),
 				"set_transaction_id %" PRIu64 " %" PRIu64,
@@ -3051,12 +3046,6 @@ int dm_tree_node_add_thin_pool_message(struct dm_tree_node *node,
 		tm->message.u.m_delete.device_id = id1;
 		tm->expected_errno = ENODATA;
 		break;
-	case DM_THIN_MESSAGE_TRIM:
-		if (!_thin_validate_device_id(id1))
-			return_0;
-		tm->message.u.m_trim.device_id = id1;
-		tm->message.u.m_trim.new_size = id2;
-		break;
 	case DM_THIN_MESSAGE_SET_TRANSACTION_ID:
 		if ((id1 + 1) != id2) {
 			log_error("New transaction id must be sequential.");