diff --git a/stocklake/nasdaqapi/data_loader.py b/stocklake/nasdaqapi/data_loader.py
index 6fd97af..f2c3487 100644
--- a/stocklake/nasdaqapi/data_loader.py
+++ b/stocklake/nasdaqapi/data_loader.py
@@ -8,7 +8,7 @@
 from stocklake.core.base_data_loader import BaseDataLoader
 from stocklake.core.constants import CACHE_DIR
 from stocklake.nasdaqapi.constants import Exchange
-from stocklake.nasdaqapi.entities import RawNasdaqApiSymbolData
+from stocklake.nasdaqapi.entities import RawNasdaqApiData
 from stocklake.nasdaqapi.utils import nasdaq_api_get_request
 from stocklake.stores.artifact.local_artifact_repo import LocalArtifactRepository
 
@@ -29,7 +29,7 @@ def cache_artifact_path(self) -> str:
             self._cache_artifact_repo.artifact_dir, self._cache_artifact_filename
         )
 
-    def download(self) -> List[RawNasdaqApiSymbolData]:
+    def download(self) -> List[RawNasdaqApiData]:
         logger.info(
             f"Loading {self.exchange_name.upper()} symbols data from `https://www.nasdaq.com/`"
         )
@@ -40,4 +40,4 @@ def download(self) -> List[RawNasdaqApiSymbolData]:
             with open(local_file, "w") as f:
                 json.dump(data, f)
             self._cache_artifact_repo.save_artifact(local_file)
-        return data
+        return [RawNasdaqApiData(**d) for d in data]
diff --git a/stocklake/nasdaqapi/entities.py b/stocklake/nasdaqapi/entities.py
index 94bbcd6..f770f72 100644
--- a/stocklake/nasdaqapi/entities.py
+++ b/stocklake/nasdaqapi/entities.py
@@ -1,7 +1,25 @@
 from typing import List, Optional, TypedDict
 
+from pydantic import BaseModel, ConfigDict
 
-class RawNasdaqApiSymbolData(TypedDict):
+
+class TD_RawNasdaqApiData(TypedDict):
+    symbol: str
+    name: str
+    lastsale: str
+    netchange: str
+    pctchange: str
+    volume: str
+    marketCap: str
+    country: str
+    ipoyear: str
+    industry: str
+    sector: str
+    url: str
+
+
+class RawNasdaqApiData(BaseModel):
+    model_config = ConfigDict(extra="forbid")
     symbol: str
     name: str
     lastsale: str
@@ -16,7 +34,7 @@ class RawNasdaqApiSymbolData(TypedDict):
     url: str
 
 
-class NasdaqApiSymbolData(TypedDict):
+class NasdaqApiDataBase(BaseModel):
     symbol: str
     exchange: str
     name: str
@@ -32,10 +50,26 @@ class NasdaqApiSymbolData(TypedDict):
     url: str
 
 
+class PreprocessedNasdaqApiData(NasdaqApiDataBase):
+    pass
+
+
+class NasdaqApiDataCreate(NasdaqApiDataBase):
+    pass
+
+
+class NasdaqApiData(NasdaqApiDataBase):
+    model_config = ConfigDict(from_attributes=True)
+
+    id: int
+    created_at: int
+    updated_at: int
+
+
 class _ResponseData(TypedDict):
     asOf: str
-    headers: RawNasdaqApiSymbolData
-    rows: List[RawNasdaqApiSymbolData]
+    headers: TD_RawNasdaqApiData
+    rows: List[TD_RawNasdaqApiData]
 
 
 class NasdaqAPIResponse(TypedDict):
diff --git a/stocklake/nasdaqapi/preprocessor.py b/stocklake/nasdaqapi/preprocessor.py
index 9227c80..f914e04 100644
--- a/stocklake/nasdaqapi/preprocessor.py
+++ b/stocklake/nasdaqapi/preprocessor.py
@@ -2,47 +2,44 @@
 
 from stocklake.core.base_preprocessor import BasePreprocessor
 from stocklake.nasdaqapi.constants import Exchange
-from stocklake.nasdaqapi.entities import NasdaqApiSymbolData, RawNasdaqApiSymbolData
+from stocklake.nasdaqapi.entities import PreprocessedNasdaqApiData, RawNasdaqApiData
 
 
 class NASDAQSymbolsPreprocessor(BasePreprocessor):
     def process(
-        self, exchange: Exchange, data: List[RawNasdaqApiSymbolData]
-    ) -> List[NasdaqApiSymbolData]:
-        processed_data: List[NasdaqApiSymbolData] = []
-        for data_dic in data:
-            _data: NasdaqApiSymbolData = {
-                "symbol": data_dic["symbol"],
+        self, exchange: Exchange, data: List[RawNasdaqApiData]
+    ) -> List[PreprocessedNasdaqApiData]:
+        processed_data = []
+        for d in data:
+            _data = {
+                "symbol": d.symbol,
                 "exchange": exchange,
-                "name": data_dic["name"],
-                "last_sale": float(
-                    data_dic["lastsale"].replace("$", "").replace(",", "")
-                ),
+                "name": d.name,
+                "last_sale": float(d.lastsale.replace("$", "").replace(",", "")),
                 "pct_change": (
-                    None
-                    if data_dic["pctchange"] == ""
-                    else float(data_dic["pctchange"].replace("%", ""))
+                    None if d.pctchange == "" else float(d.pctchange.replace("%", ""))
                 ),
-                "net_change": float(data_dic["netchange"]),
-                "volume": float(data_dic["volume"]),
-                "marketcap": self._market_cap(data_dic),
-                "country": data_dic["country"],
-                "ipo_year": self._ipo_year(data_dic),
-                "industry": data_dic["industry"],
-                "sector": data_dic["sector"],
-                "url": data_dic["url"],
+                "net_change": float(d.netchange),
+                "volume": float(d.volume),
+                "marketcap": self._market_cap(d),
+                "country": d.country,
+                "ipo_year": self._ipo_year(d),
+                "industry": d.industry,
+                "sector": d.sector,
+                "url": d.url,
             }
-            processed_data.append(_data)
+            # NOTE: We ignore arg-type mypy error here, because of this bug https://github.com/python/mypy/issues/5382.
+            processed_data.append(PreprocessedNasdaqApiData(**_data))  # type: ignore
         return processed_data
 
-    def _ipo_year(self, data_dic: RawNasdaqApiSymbolData) -> int:
-        ipo_year = data_dic["ipoyear"]
+    def _ipo_year(self, data: RawNasdaqApiData) -> int:
+        ipo_year = data.ipoyear
         if ipo_year == "":
             return 0
         return int(ipo_year)
 
-    def _market_cap(self, data_dic: RawNasdaqApiSymbolData) -> float:
-        market_cap = data_dic["marketCap"].replace(",", "")
+    def _market_cap(self, data: RawNasdaqApiData) -> float:
+        market_cap = data.marketCap.replace(",", "")
         if market_cap == "":
             return 0.0
         return float(market_cap)
diff --git a/stocklake/nasdaqapi/stores.py b/stocklake/nasdaqapi/stores.py
index 0b91e70..6041846 100644
--- a/stocklake/nasdaqapi/stores.py
+++ b/stocklake/nasdaqapi/stores.py
@@ -6,11 +6,11 @@
 from stocklake.core.base_store import BaseStore
 from stocklake.core.constants import DATA_DIR
 from stocklake.exceptions import StockLakeException
+from stocklake.nasdaqapi import entities
 from stocklake.nasdaqapi.constants import Exchange
-from stocklake.nasdaqapi.entities import NasdaqApiSymbolData
 from stocklake.stores.artifact.local_artifact_repo import LocalArtifactRepository
 from stocklake.stores.constants import StoreType
-from stocklake.stores.db import models, schemas
+from stocklake.stores.db import models
 from stocklake.stores.db.database import (
     DATABASE_SESSION_TYPE,
     local_session,
@@ -31,13 +31,13 @@ def save(
         self,
         store_type: StoreType,
         exchange: Exchange,
-        data: List[NasdaqApiSymbolData],
+        data: List[entities.PreprocessedNasdaqApiData],
     ) -> str:
         if store_type == StoreType.LOCAL_ARTIFACT:
             repository = LocalArtifactRepository(SAVE_ARTIFACTS_DIR)
             with tempfile.TemporaryDirectory() as tmpdir:
                 csv_file_path = os.path.join(tmpdir, f"{exchange}_data.csv")
-                save_data_to_csv(data, csv_file_path)
+                save_data_to_csv([d.model_dump() for d in data], csv_file_path)
                 repository.save_artifact(csv_file_path)
             return repository.list_artifacts()[0].path
         elif store_type == StoreType.POSTGRESQL:
@@ -45,7 +45,9 @@ def save(
                 raise StockLakeException("`sqlalchemy_session` is None.")
             sqlstore = NasdaqApiSQLAlchemyStore(exchange, self.sqlalchemy_session)
             sqlstore.delete()
-            sqlstore.create([schemas.NasdaqStockCreate(**d) for d in data])
+            sqlstore.create(
+                [entities.NasdaqApiDataCreate(**d.model_dump()) for d in data]
+            )
             return os.path.join(
                 safe_database_url_from_sessionmaker(self.sqlalchemy_session),
                 models.NasdaqApiData.__tablename__,
@@ -59,7 +61,9 @@ def __init__(self, exchange: Exchange, session: DATABASE_SESSION_TYPE):
         self.exchange = exchange
         self.session = session
 
-    def create(self, data: schemas.NasdaqStockCreate | List[schemas.NasdaqStockCreate]):
+    def create(
+        self, data: entities.NasdaqApiDataCreate | List[entities.NasdaqApiDataCreate]
+    ):
         with self.session() as session, session.begin():
             if isinstance(data, list):
                 session.add_all([models.NasdaqApiData(**d.model_dump()) for d in data])
diff --git a/stocklake/stores/db/schemas.py b/stocklake/stores/db/schemas.py
index 8f1ba7a..670ff6f 100644
--- a/stocklake/stores/db/schemas.py
+++ b/stocklake/stores/db/schemas.py
@@ -3,34 +3,6 @@
 from pydantic import BaseModel, ConfigDict
 
 
-class NasdaqStockBase(BaseModel):
-    symbol: str
-    exchange: str
-    name: str
-    last_sale: float
-    pct_change: Optional[float]
-    net_change: float
-    volume: float
-    marketcap: float
-    country: str
-    ipo_year: int
-    industry: str
-    sector: str
-    url: str
-
-
-class NasdaqStockCreate(NasdaqStockBase):
-    pass
-
-
-class NasdaqStock(NasdaqStockBase):
-    model_config = ConfigDict(from_attributes=True)
-
-    id: int
-    created_at: int
-    updated_at: int
-
-
 class PolygonFinancialsDataBase(BaseModel):
     # financials data
     # - balance sheet
diff --git a/tests/nasdaqapi/test_data_loader.py b/tests/nasdaqapi/test_data_loader.py
index cdd5e49..17685e1 100644
--- a/tests/nasdaqapi/test_data_loader.py
+++ b/tests/nasdaqapi/test_data_loader.py
@@ -31,10 +31,10 @@ def MockNasdaqAPIServer():
 
 
 @pytest.mark.parametrize("exchange_name", Exchange.exchanges())
-def test_data_loader(exchange_name, tmpdir, MockNasdaqAPIServer):
+def test_download(exchange_name, tmpdir, MockNasdaqAPIServer):
     data_loader = NASDAQSymbolsDataLoader(exchange_name=exchange_name, cache_dir=tmpdir)
     data = data_loader.download()
     assert os.path.exists(data_loader.cache_artifact_path)
-    for row in data:
+    for d in data:
         for col in expected_cols:
-            assert col in row
+            assert col in d.model_dump()
diff --git a/tests/nasdaqapi/test_preprocessor.py b/tests/nasdaqapi/test_preprocessor.py
index d49d947..6d32e4f 100644
--- a/tests/nasdaqapi/test_preprocessor.py
+++ b/tests/nasdaqapi/test_preprocessor.py
@@ -8,8 +8,8 @@ def test_process(tmpdir, MockNasdaqAPIServer):  # noqa: F811
     data_loader = NASDAQSymbolsDataLoader(exchange_name=Exchange.AMEX, cache_dir=tmpdir)
     preprocessor = NASDAQSymbolsPreprocessor()
     data = preprocessor.process(exchange=Exchange.NASDAQ, data=data_loader.download())
-    for data_dic in data:
-        for key, val in data_dic.items():
+    for d in data:
+        for key, val in d.model_dump().items():
             if key in ["last_sale", "net_change", "pct_change", "marketcap", "volume"]:
                 assert isinstance(val, float)
             elif key in ["ipo_year"]:
diff --git a/tests/nasdaqapi/test_stores.py b/tests/nasdaqapi/test_stores.py
index e545a2b..f9d6881 100644
--- a/tests/nasdaqapi/test_stores.py
+++ b/tests/nasdaqapi/test_stores.py
@@ -5,6 +5,7 @@
 
 from conftest import SessionLocal  # noqa: F401
 from stocklake.nasdaqapi.constants import Exchange
+from stocklake.nasdaqapi.entities import NasdaqApiDataCreate
 from stocklake.nasdaqapi.stores import (
     SAVE_ARTIFACTS_DIR,
     NasdaqApiSQLAlchemyStore,
@@ -12,7 +13,6 @@
 )
 from stocklake.stores.constants import StoreType
 from stocklake.stores.db.models import NasdaqApiData
-from stocklake.stores.db.schemas import NasdaqStockCreate
 
 
 def test_nasdaqdatastore_local_artifact():
@@ -22,21 +22,23 @@ def test_nasdaqdatastore_local_artifact():
         StoreType.LOCAL_ARTIFACT,
         exchange_name,
         [
-            {
-                "symbol": "TEST",
-                "exchange": Exchange.NASDAQ,
-                "name": "Test Company",
-                "last_sale": 0.88,
-                "pct_change": 0.5,
-                "net_change": 0.35,
-                "volume": 100.5,
-                "marketcap": 0.75,
-                "country": "US",
-                "ipo_year": 1999,
-                "industry": "Tech",
-                "sector": "Health",
-                "url": "https://example.com",
-            }
+            NasdaqApiDataCreate(
+                **{
+                    "symbol": "TEST",
+                    "exchange": Exchange.NASDAQ,
+                    "name": "Test Company",
+                    "last_sale": 0.88,
+                    "pct_change": 0.5,
+                    "net_change": 0.35,
+                    "volume": 100.5,
+                    "marketcap": 0.75,
+                    "country": "US",
+                    "ipo_year": 1999,
+                    "industry": "Tech",
+                    "sector": "Health",
+                    "url": "https://example.com",
+                }
+            )
         ],
     )
     assert os.path.exists(os.path.join(SAVE_ARTIFACTS_DIR, f"{exchange_name}_data.csv"))
@@ -49,21 +51,23 @@ def test_nasdaqdatastore_postgresql(SessionLocal):  # noqa: F811
         StoreType.POSTGRESQL,
         exchange_name,
         [
-            {
-                "symbol": "TEST",
-                "exchange": Exchange.NASDAQ,
-                "name": "Test Company",
-                "last_sale": 0.88,
-                "pct_change": 0.5,
-                "net_change": 0.35,
-                "volume": 100.5,
-                "marketcap": 0.75,
-                "country": "US",
-                "ipo_year": 1999,
-                "industry": "Tech",
-                "sector": "Health",
-                "url": "https://example.com",
-            }
+            NasdaqApiDataCreate(
+                **{
+                    "symbol": "TEST",
+                    "exchange": Exchange.NASDAQ,
+                    "name": "Test Company",
+                    "last_sale": 0.88,
+                    "pct_change": 0.5,
+                    "net_change": 0.35,
+                    "volume": 100.5,
+                    "marketcap": 0.75,
+                    "country": "US",
+                    "ipo_year": 1999,
+                    "industry": "Tech",
+                    "sector": "Health",
+                    "url": "https://example.com",
+                }
+            )
         ],
     )
     with SessionLocal() as session, session.begin():
@@ -91,7 +95,7 @@ def test_NasdaqAPISQLAlchemyStore_create(SessionLocal):  # noqa: F811
     }
 
     # Add item
-    store.create(NasdaqStockCreate(**data))
+    store.create(NasdaqApiDataCreate(**data))
     with SessionLocal() as session, session.begin():
         res = session.query(NasdaqApiData).all()
         assert len(res) == 1
@@ -117,7 +121,7 @@ def test_NasdaqAPISQLAlchemyStore_create(SessionLocal):  # noqa: F811
     data2["symbol"] = "TEST2"
     data3 = copy.deepcopy(data)
     data3["symbol"] = "TEST3"
-    store.create([NasdaqStockCreate(**data2), NasdaqStockCreate(**data3)])
+    store.create([NasdaqApiDataCreate(**data2), NasdaqApiDataCreate(**data3)])
     with SessionLocal() as session, session.begin():
         assert len(session.query(NasdaqApiData).all()) == 3
 
@@ -142,7 +146,7 @@ def test_NasdaqAPISQLAlchemyStore_delete(exchange, SessionLocal):  # noqa: F811
     }
 
     # Add item
-    store.create(NasdaqStockCreate(**data))
+    store.create(NasdaqApiDataCreate(**data))
     with SessionLocal() as session, session.begin():
         res = session.query(NasdaqApiData).all()
         assert len(res) == 1