diff --git a/CHANGELOG.md b/CHANGELOG.md
index 364194c1..1ad163df 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@ and this project adheres to
 - ⬆️(dependencies) update django to v5.2.13 [SECURITY]
 - 🔒(backend) rely on backend to allow participant update their metadata
 - 🐛(summary) fix failure webhook notification #1233
+- 🐛(summary) relax whisperX payload format #1233
 
 ## [1.13.0] - 2026-03-31
 
diff --git a/src/summary/summary/core/shared_models.py b/src/summary/summary/core/shared_models.py
index 340a9959..043ea759 100644
--- a/src/summary/summary/core/shared_models.py
+++ b/src/summary/summary/core/shared_models.py
@@ -9,21 +9,33 @@ class WordSegment(BaseModel):
     """Word segment model for transcription tasks."""
 
     word: str = Field(title="Word")
-    start: float = Field(title="Start Time", description="Start time in seconds.")
-    end: float = Field(title="End Time", description="End time in seconds.")
+    start: float | None = Field(
+        default=None, title="Start Time", description="Start time in seconds."
+    )
+    end: float | None = Field(
+        default=None, title="End Time", description="End time in seconds."
+    )
     score: float | None = Field(
-        title="Confidence Score", description="Confidence score for the word segment."
+        default=None,
+        title="Confidence Score",
+        description="Confidence score for the word segment.",
     )
     speaker: str | None = Field(
-        title="Speaker", description="Speaker identifier for the word segment."
+        default=None,
+        title="Speaker",
+        description="Speaker identifier for the word segment.",
     )
 
 
 class Segment(BaseModel):
     """Segment model for transcription tasks."""
 
-    start: float = Field(title="Start Time", description="Start time in seconds.")
-    end: float = Field(title="End Time", description="End time in seconds.")
+    start: float | None = Field(
+        default=None, title="Start Time", description="Start time in seconds."
+    )
+    end: float | None = Field(
+        default=None, title="End Time", description="End time in seconds."
+    )
     text: str = Field(
         title="Segment Text", description="Transcribed text for the segment."
     )
@@ -31,7 +43,7 @@ class Segment(BaseModel):
         title="Word Segments", description="List of word segments within the segment."
     )
     speaker: str | None = Field(
-        title="Speaker", description="Speaker identifier for the segment."
+        default=None, title="Speaker", description="Speaker identifier for the segment."
     )
 
 
diff --git a/src/summary/tests/models/__init__.py b/src/summary/tests/models/__init__.py
new file mode 100644
index 00000000..7c3c4e3c
--- /dev/null
+++ b/src/summary/tests/models/__init__.py
@@ -0,0 +1 @@
+"""Tests for models."""
diff --git a/src/summary/tests/models/test_whisper_x_response.py b/src/summary/tests/models/test_whisper_x_response.py
new file mode 100644
index 00000000..86c33323
--- /dev/null
+++ b/src/summary/tests/models/test_whisper_x_response.py
@@ -0,0 +1,60 @@
+"""Tests for WhisperXResponse."""
+
+from summary.core.shared_models import WhisperXResponse
+
+
+def test_whisper_x_response_partial_response_is_valid():
+    """A partial response from WhisperX is valid.
+
+    Sometimes WhisperX Api doesn't return all the data and timestamps,
+    we don't want to fail the whole process.
+    """
+    WhisperXResponse.model_validate(
+        {
+            "segments": [
+                {
+                    "start": 1.135,
+                    "end": 7.3,
+                    "text": " Test 1, 2, 3... Est-?",
+                    "words": [
+                        {
+                            "word": "Test",
+                            "start": 1.135,
+                            "end": 2.216,
+                            "score": 0.654,
+                            "speaker": "SPEAKER_00",
+                        },
+                        {
+                            "word": "1,",
+                            "start": None,
+                            "end": None,
+                            "score": None,
+                            "speaker": None,
+                        },
+                        {
+                            "word": "2,",
+                            "start": None,
+                            "end": None,
+                            "score": None,
+                            "speaker": None,
+                        },
+                        {
+                            "word": "3...",
+                        },
+                    ],
+                    "speaker": "SPEAKER_00",
+                }
+            ],
+            "word_segments": [
+                {
+                    "word": "Test",
+                    "start": 1.135,
+                    "end": 2.216,
+                    "score": 0.654,
+                    "speaker": "SPEAKER_00",
+                },
+                {"word": "1,"},
+                {"word": "?"},
+            ],
+        }
+    )