diff --git a/lock/types.proto b/lock/types.proto
index 30a9607..fea7fe6 100644
--- a/lock/types.proto
+++ b/lock/types.proto
@@ -7,8 +7,11 @@ option csharp_namespace = "Neo.FileStorage.API.Lock";
 
 import "refs/types.proto";
 
-// Lock keeps record of objects that are locked.
+// Lock objects protects a list of objects from being deleted. Lifetime of the
+// lock object is limited similar to regular objects in
+// `__NEOFS__EXPIRATION_EPOCH` attribute.
 message Lock {
-  // List of objects to be locked.
+  // List of objects to lock. Must not be empty or carry empty IDs.
+  // All members must be of the `REGULAR` type.
   repeated neo.fs.v2.refs.ObjectID members = 1 [json_name = "members"];
 }
diff --git a/object/types.proto b/object/types.proto
index dc0bb69..2980b39 100644
--- a/object/types.proto
+++ b/object/types.proto
@@ -185,13 +185,8 @@ message Header {
 // `ObjectID` will change if header or payload changes. It's calculated as a
 // hash of header field, which contains hash of object's payload.
 //
-// Payload format depends on object type specified in the header:
-// * **LOCK** \
-// Must be encoded message of type `Lock` in Protocol Buffers binary format
-// with direct field order. Member list must no be empty or carry empty IDs.
-// All members must regular objects (`REGULAR` type). Lifetime of the lock
-// object is limited similar to regular objects in `__NEOFS__EXPIRATION_EPOCH`
-// attribute.
+// For non-regular object types payload format depends on object type specified
+// in the header.
 message Object {
   // Object's unique identifier.
   neo.fs.v2.refs.ObjectID object_id = 1 [json_name = "objectID"];