diff --git a/frappe/api.py b/frappe/api.py
index 36d51e894c..636c6b2888 100644
--- a/frappe/api.py
+++ b/frappe/api.py
@@ -82,7 +82,7 @@ def handle():
 				if frappe.local.request.method=="PUT":
 					data = get_request_form_data()
 
-					doc = frappe.get_doc(doctype, name)
+					doc = frappe.get_doc(doctype, name, for_update=True)
 
 					if "flags" in data:
 						del data["flags"]
diff --git a/frappe/utils/nestedset.py b/frappe/utils/nestedset.py
index 3c024c40e4..4a65140449 100644
--- a/frappe/utils/nestedset.py
+++ b/frappe/utils/nestedset.py
@@ -57,7 +57,7 @@ def update_add_node(doc, parent, parent_field):
 
 	# get the last sibling of the parent
 	if parent:
-		left, right = frappe.db.sql("select lft, rgt from `tab{0}` where name=%s"
+		left, right = frappe.db.sql("select lft, rgt from `tab{0}` where name=%s for update"
 			.format(doctype), parent)[0]
 		validate_loop(doc.doctype, doc.name, left, right)
 	else: # root
@@ -89,7 +89,7 @@ def update_move_node(doc, parent_field):
 
 	if parent:
 		new_parent = frappe.db.sql("""select lft, rgt from `tab{0}`
-			where name = %s""".format(doc.doctype), parent, as_dict=1)[0]
+			where name = %s for update""".format(doc.doctype), parent, as_dict=1)[0]
 
 		validate_loop(doc.doctype, doc.name, new_parent.lft, new_parent.rgt)
 
@@ -108,7 +108,7 @@ def update_move_node(doc, parent_field):
 
 	if parent:
 		new_parent = frappe.db.sql("""select lft, rgt from `tab%s`
-			where name = %s""" % (doc.doctype, '%s'), parent, as_dict=1)[0]
+			where name = %s for update""" % (doc.doctype, '%s'), parent, as_dict=1)[0]
 
 
 		# set parent lft, rgt