diff --git a/object/service.proto b/object/service.proto
index 17be2c1..1d08ff5 100644
--- a/object/service.proto
+++ b/object/service.proto
@@ -311,9 +311,17 @@ message PutRequest {
       // Object's Header
       Header header = 3;
 
-      // Number of the object copies to store within the RPC call. By default
+      // Number of copies of the object to store within the RPC call. By default,
       // object is processed according to the container's placement policy.
-      uint32 copies_number = 4;
+      // Can be one of:
+      // 1. A single number; applied to the whole request and is treated as
+      // a minimal number of nodes that must store an object to complete the
+      // request successfully.
+      // 2. An ordered array; every number is treated as a minimal number of
+      // nodes in a corresponding placement vector that must store an object
+      // to complete the request successfully. The length MUST equal the placement
+      // vectors number, otherwise request is considered malformed.
+      repeated uint32 copies_number = 4;
     }
     // Single message in the request stream.
     oneof object_part {
diff --git a/proto-docs/object.md b/proto-docs/object.md
index b25fa57..8b5f460 100644
--- a/proto-docs/object.md
+++ b/proto-docs/object.md
@@ -658,7 +658,7 @@ are not set, they will be calculated by a peer node.
 | object_id | [neo.fs.v2.refs.ObjectID](#neo.fs.v2.refs.ObjectID) |  | ObjectID if available. |
 | signature | [neo.fs.v2.refs.Signature](#neo.fs.v2.refs.Signature) |  | Object signature if available |
 | header | [Header](#neo.fs.v2.object.Header) |  | Object's Header |
-| copies_number | [uint32](#uint32) |  | Number of the object copies to store within the RPC call. By default object is processed according to the container's placement policy. |
+| copies_number | [uint32](#uint32) | repeated | Number of copies of the object to store within the RPC call. By default, object is processed according to the container's placement policy. Can be one of: 1. A single number; applied to the whole request and is treated as a minimal number of nodes that must store an object to complete the request successfully. 2. An ordered array; every number is treated as a minimal number of nodes in a corresponding placement vector that must store an object to complete the request successfully. The length MUST equal the placement vectors number, otherwise request is considered malformed. |
 
 
 <a name="neo.fs.v2.object.PutResponse"></a>