diff --git a/dataconnect/service/default.py b/dataconnect/service/default.py
index d309fda..b2c6fff 100644
--- a/dataconnect/service/default.py
+++ b/dataconnect/service/default.py
@@ -6,7 +6,6 @@
 
 import pandas as pd
 
-from dataconnect.exceptions import ErrorDetail
 from dataconnect.models import Dataset, DatasetVersion, PaginatedResponse, Pagination, StudiesResult
 from dataconnect.service.base import DataConnectService
 from dataconnect.service.error_handler import translate_error
@@ -16,7 +15,6 @@
     resource_to_fetched_data,
     resource_to_study,
 )
-from dataconnect.service.validators import validate_positive_int, validate_uuid
 from dataconnect.transport.base import Transport
 from dataconnect.transport.errors import TransportError
 from dataconnect.transport.models import DatasetTicket, ResourceQuery
@@ -89,37 +87,6 @@ def get_dataset_versions(self, dataset_uuid: UUID) -> list[DatasetVersion]:
     def fetch_data(self, dataset_uuid: UUID, first_n_rows: int | None = None) -> pd.DataFrame:
         """Fetch data for a dataset"""
 
-        validate_uuid(
-            dataset_uuid,
-            field_name="dataset_uuid",
-            error_code="VAL_C_DATASET_UUID",
-            message="Invalid dataset_uuid.",
-            details=[
-                ErrorDetail(
-                    field="dataset_uuid",
-                    message="dataset_uuid must be a valid UUID.",
-                    expected="Review and provide the correct dataset_uuid.",
-                )
-            ],
-        )
-
-        if first_n_rows is not None:
-            validate_positive_int(
-                first_n_rows,
-                field_name="first_n_rows",
-                error_code="VAL_C_FIRST_N_ROWS",
-                message="Invalid first_n_rows.",
-                details=[
-                    ErrorDetail(
-                        field="first_n_rows",
-                        message=(f"Received {first_n_rows} for first_n_rows, which is not a positive integer."),
-                        expected=(
-                            "Set first_n_rows to 1 or greater, or omit the parameter to retrieve the full dataset"
-                        ),
-                    )
-                ],
-            )
-
         ticket = DatasetTicket(
             dataset_uuid=str(dataset_uuid),
             limit=first_n_rows,
diff --git a/tests/test_fetch_data.py b/tests/test_fetch_data.py
index 0f5396e..776c7d0 100644
--- a/tests/test_fetch_data.py
+++ b/tests/test_fetch_data.py
@@ -13,7 +13,6 @@
     AuthorizationError,
     NotFoundError,
     ServerError,
-    ValidationError,
 )
 from dataconnect.service.default import DefaultDataConnectService
 from dataconnect.transport.errors import (
@@ -120,86 +119,6 @@ def test_fetch_data_returns_empty_dataframe_for_empty_table() -> None:
     assert "col" in result.columns
 
 
-# ---------------------------------------------------------------------------
-# Validation — dataset_uuid
-# ---------------------------------------------------------------------------
-
-
-def test_fetch_data_raises_validation_error_on_none_uuid() -> None:
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data(None)  # type: ignore[arg-type]
-
-    assert exc_info.value.error_code == "VAL_C_DATASET_UUID"
-
-
-def test_fetch_data_raises_validation_error_on_zero_uuid() -> None:
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data(UUID(int=0))
-
-    assert exc_info.value.error_code == "VAL_C_DATASET_UUID"
-
-
-def test_fetch_data_raises_validation_error_on_string_uuid() -> None:
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data("073410b6-79be-3e7d-ae37-92f6e054013e")  # type: ignore[arg-type]
-
-    assert exc_info.value.error_code == "VAL_C_DATASET_UUID"
-
-
-# ---------------------------------------------------------------------------
-# Validation — first_n_rows
-# ---------------------------------------------------------------------------
-
-
-def test_fetch_data_raises_validation_error_on_zero_first_n_rows() -> None:
-    dataset_uuid = UUID("073410b6-79be-3e7d-ae37-92f6e054013e")
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data(dataset_uuid, first_n_rows=0)
-
-    assert exc_info.value.error_code == "VAL_C_FIRST_N_ROWS"
-    assert exc_info.value.details is not None
-    assert exc_info.value.details[0].field == "first_n_rows"
-
-
-def test_fetch_data_raises_validation_error_on_negative_first_n_rows() -> None:
-    dataset_uuid = UUID("073410b6-79be-3e7d-ae37-92f6e054013e")
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data(dataset_uuid, first_n_rows=-5)
-
-    assert exc_info.value.error_code == "VAL_C_FIRST_N_ROWS"
-
-
-def test_fetch_data_raises_validation_error_on_non_int_first_n_rows() -> None:
-    dataset_uuid = UUID("073410b6-79be-3e7d-ae37-92f6e054013e")
-    transport = _FakeTransport(data_table=_make_ipc_table({"x": [1]}))
-    service = DefaultDataConnectService(transport)
-
-    with pytest.raises(ValidationError) as exc_info:
-        service.fetch_data(dataset_uuid, first_n_rows="abc")  # type: ignore[arg-type]
-
-    assert exc_info.value.error_code == "VAL_C_FIRST_N_ROWS"
-
-
-# ---------------------------------------------------------------------------
-# Transport-error translation
-# ---------------------------------------------------------------------------
-
-
 def test_fetch_data_translates_authentication_error() -> None:
     dataset_uuid = UUID("073410b6-79be-3e7d-ae37-92f6e054013e")
     transport = _FakeTransport(