WHATS_NEW                  | 1 +
 lib/activate/dev_manager.c | 5 +++++
 2 files changed, 6 insertions(+)

diff --git a/WHATS_NEW b/WHATS_NEW
index d1f4530..00b84f9 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -2,6 +2,7 @@ Version 2.02.187 -
 ===================================
   Prevent creating VGs with PVs with different logical block sizes.
   Pvmove runs in exlusively activating mode for exclusively active LVs.
+  Activate thin-pool layered volume as 'read-only' device.
   Enhance validation for thin and cache pool conversion and swapping.
 
 Version 2.02.186 - 27th August 2019
diff --git a/lib/activate/dev_manager.c b/lib/activate/dev_manager.c
index dc64159..56608e3 100644
--- a/lib/activate/dev_manager.c
+++ b/lib/activate/dev_manager.c
@@ -84,6 +84,11 @@ int read_only_lv(const struct logical_volume *lv, const struct lv_activate_opts
 	if (lv_is_raid_image(lv) || lv_is_raid_metadata(lv))
 		return 0; /* Keep RAID SubLvs writable */
 
+	if (!layer) {
+		if (lv_is_thin_pool(lv))
+			return 1;
+	}
+
 	return (laopts->read_only || !(lv->status & LVM_WRITE));
 }