diff --git a/CHANGELOG.md b/CHANGELOG.md
index d659165fc..f2eb27add 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -51,6 +51,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Fixed `TermsQuery` `_name` and `boost` type ([#984](https://github.com/opensearch-project/opensearch-api-specification/pull/984))
 - Fixed SearchResult::hits specification ([#1011](https://github.com/opensearch-project/opensearch-api-specification/pull/1011))
 - Fixed the type of `Hit`'s `matched_queries` to be either an array or a map to support when `include_named_queries_score` is `true` ([#1015](https://github.com/opensearch-project/opensearch-api-specification/pull/1015))
+- Fixed `ShardFailure.primary` field to be not required ([#1039](https://github.com/opensearch-project/opensearch-api-specification/pull/1039))
 
 ### Changed
 - Changed schema of `NodeInfoSearchPipelines`'s `response_processors` & `request_processors` to use `NodeInfoSearchPipelineProcessor` instead of `NodeInfoIngestProcessor` ([#922](https://github.com/opensearch-project/opensearch-api-specification/pull/922))
diff --git a/spec/schemas/_common.yaml b/spec/schemas/_common.yaml
index e72a86823..d3a002b76 100644
--- a/spec/schemas/_common.yaml
+++ b/spec/schemas/_common.yaml
@@ -335,7 +335,6 @@ components:
         primary:
           type: boolean
       required:
-        - primary
         - reason
         - shard
     ErrorCause: