diff --git a/litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py b/litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py
index 74d5ad330e5..dd22669ac21 100644
--- a/litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py
+++ b/litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py
@@ -1230,18 +1230,26 @@ class VertexGeminiConfig(VertexAIBaseConfig, BaseConfig):
             "IMAGE_PROHIBITED_CONTENT": "The token generation was stopped as the response was flagged for prohibited image content.",
         }
 
+    _GEMINI_FINISH_REASON_KEYS = frozenset({
+        "STOP", "MAX_TOKENS", "SAFETY", "RECITATION", "FINISH_REASON_UNSPECIFIED",
+        "MALFORMED_FUNCTION_CALL", "LANGUAGE", "OTHER", "BLOCKLIST",
+        "PROHIBITED_CONTENT", "SPII", "IMAGE_SAFETY", "IMAGE_PROHIBITED_CONTENT",
+        "TOO_MANY_TOOL_CALLS", "MALFORMED_RESPONSE",
+    })
+
     @staticmethod
     def get_finish_reason_mapping() -> Dict[str, OpenAIChatCompletionFinishReason]:
         """
-        Return Dictionary of finish reasons which indicate response was flagged
-
-        and what it means.
-
-        Delegates to the centralized _FINISH_REASON_MAP to avoid duplication.
+        Return Dictionary of Gemini/Vertex AI finish reasons and their
+        OpenAI-compatible mappings.
         """
         from litellm.litellm_core_utils.core_helpers import _FINISH_REASON_MAP
 
-        return dict(_FINISH_REASON_MAP)
+        return {
+            k: v
+            for k, v in _FINISH_REASON_MAP.items()
+            if k in VertexGeminiConfig._GEMINI_FINISH_REASON_KEYS
+        }
 
     def translate_exception_str(self, exception_string: str):
         if (
diff --git a/litellm/types/utils.py b/litellm/types/utils.py
index 50960134695..ecf4669f3d0 100644
--- a/litellm/types/utils.py
+++ b/litellm/types/utils.py
@@ -1329,7 +1329,7 @@ class Choices(SafeAttributeModel, OpenAIObject):
             mapped = map_finish_reason(finish_reason)
             params["finish_reason"] = mapped
             if finish_reason != mapped:
-                provider_specific_fields = provider_specific_fields or {}
+                provider_specific_fields = dict(provider_specific_fields) if provider_specific_fields else {}
                 provider_specific_fields["native_finish_reason"] = finish_reason
         else:
             params["finish_reason"] = "stop"