diff --git a/CHANGELOG.md b/CHANGELOG.md
index 485b6453caa..9b9022d5f7d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
 - Updated get_tracer to return an empty string when passed an invalid name
   ([#1854](https://github.com/open-telemetry/opentelemetry-python/pull/1854))
+- Changed AttributeValue sequences to warn mypy users on adding None values to array
+  ([#1855](https://github.com/open-telemetry/opentelemetry-python/pull/1855))
 
 ## [1.2.0, 0.21b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.2.0-0.21b0) - 2021-05-11
 
diff --git a/opentelemetry-api/src/opentelemetry/util/types.py b/opentelemetry-api/src/opentelemetry/util/types.py
index ec72a287042..be171ef0ea8 100644
--- a/opentelemetry-api/src/opentelemetry/util/types.py
+++ b/opentelemetry-api/src/opentelemetry/util/types.py
@@ -20,10 +20,10 @@
     bool,
     int,
     float,
-    Sequence[Optional[str]],
-    Sequence[Optional[bool]],
-    Sequence[Optional[int]],
-    Sequence[Optional[float]],
+    Sequence[str],
+    Sequence[bool],
+    Sequence[int],
+    Sequence[float],
 ]
 Attributes = Optional[Mapping[str, AttributeValue]]
 AttributesAsKey = Tuple[