diff --git a/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributes.java b/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributes.java
index 165c9ffe2e2..539fc2f6393 100644
--- a/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributes.java
+++ b/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributes.java
@@ -41,7 +41,7 @@ public AttributesBuilder toBuilder() {
     return new ArrayBackedAttributesBuilder(new ArrayList<>(data()));
   }
 
-  @SuppressWarnings("unchecked")
+  @SuppressWarnings("unchecked") // safe cast: values are stored internally keyed by AttributeKey<T>
   @Override
   @Nullable
   public <T> T get(AttributeKey<T> key) {
diff --git a/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributesBuilder.java b/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributesBuilder.java
index af575a61e36..1872808898a 100644
--- a/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributesBuilder.java
+++ b/api/all/src/main/java/io/opentelemetry/api/common/ArrayBackedAttributesBuilder.java
@@ -49,12 +49,11 @@ public <T> AttributesBuilder put(AttributeKey<T> key, @Nullable T value) {
 
   @Override
   @SuppressWarnings({"unchecked", "rawtypes"})
+  // Safe: Attributes guarantees iteration over matching AttributeKey<T> / value pairs.
   public AttributesBuilder putAll(Attributes attributes) {
     if (attributes == null) {
       return this;
     }
-    // Attributes must iterate over their entries with matching types for key / value, so this
-    // downcast to the raw type is safe.
     attributes.forEach((key, value) -> put((AttributeKey) key, value));
     return this;
   }