diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9374a58e62..bb88caa289 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,11 @@ Changes are grouped as follows
 - `Fixed` for any bug fixes.
 - `Security` in case of vulnerabilities.
 
+## [7.63.1] - 2024-10-10
+### Fixed
+- [Feature Preview - alpha] Dumping `HostedExtractor` `Job` and `Source` data classes creates valid JSON/YAML
+  even when unknown fields are present.
+
 ## [7.63.0] - 2024-10-10
 ### Removed
 - Removed support for Python 3.8 and 3.9.
diff --git a/cognite/client/_version.py b/cognite/client/_version.py
index d423bee540..9ba876c24b 100644
--- a/cognite/client/_version.py
+++ b/cognite/client/_version.py
@@ -1,4 +1,4 @@
 from __future__ import annotations
 
-__version__ = "7.63.0"
+__version__ = "7.63.1"
 __api_subversion__ = "20230101"
diff --git a/cognite/client/data_classes/hosted_extractors/jobs.py b/cognite/client/data_classes/hosted_extractors/jobs.py
index 3471468c9f..52ef6db302 100644
--- a/cognite/client/data_classes/hosted_extractors/jobs.py
+++ b/cognite/client/data_classes/hosted_extractors/jobs.py
@@ -310,7 +310,7 @@ def __init__(
     def dump(self, camel_case: bool = True) -> dict[str, Any]:
         output = super().dump(camel_case)
         output["format"] = self.format.dump(camel_case)
-        if isinstance(self.config, JobConfig):
+        if self.config is not None:
             output["config"] = self.config.dump(camel_case)
         return output
 
diff --git a/cognite/client/data_classes/hosted_extractors/sources.py b/cognite/client/data_classes/hosted_extractors/sources.py
index 6c9495b10c..e788a985b0 100644
--- a/cognite/client/data_classes/hosted_extractors/sources.py
+++ b/cognite/client/data_classes/hosted_extractors/sources.py
@@ -488,11 +488,11 @@ def as_write(self) -> NoReturn:
 
     def dump(self, camel_case: bool = True) -> dict[str, Any]:
         output = super().dump(camel_case)
-        if isinstance(self.authentication, MQTTAuthentication):
+        if self.authentication is not None:
             output["authentication"] = self.authentication.dump(camel_case)
-        if isinstance(self.ca_certificate, CACertificate):
+        if self.ca_certificate is not None:
             output["caCertificate" if camel_case else "ca_certificate"] = self.ca_certificate.dump(camel_case)
-        if isinstance(self.auth_certificate, AuthCertificate):
+        if self.auth_certificate is not None:
             output["authCertificate" if camel_case else "auth_certificate"] = self.auth_certificate.dump(camel_case)
         return output
 
@@ -722,11 +722,11 @@ def dump(self, camel_case: bool = True) -> dict[str, Any]:
         output["bootstrapBrokers" if camel_case else "bootstrap_brokers"] = [
             broker.dump(camel_case) for broker in self.bootstrap_brokers
         ]
-        if isinstance(self.authentication, MQTTAuthentication):
+        if self.authentication is not None:
             output["authentication"] = self.authentication.dump(camel_case)
-        if isinstance(self.ca_certificate, CACertificate):
+        if self.ca_certificate is not None:
             output["caCertificate" if camel_case else "ca_certificate"] = self.ca_certificate.dump(camel_case)
-        if isinstance(self.auth_certificate, AuthCertificate):
+        if self.auth_certificate is not None:
             output["authCertificate" if camel_case else "auth_certificate"] = self.auth_certificate.dump(camel_case)
         return output
 
@@ -901,9 +901,9 @@ def as_write(self) -> RestSourceWrite:
 
     def dump(self, camel_case: bool = True) -> dict[str, Any]:
         output = super().dump(camel_case)
-        if isinstance(self.ca_certificate, CACertificate):
+        if self.ca_certificate is not None:
             output["caCertificate" if camel_case else "ca_certificate"] = self.ca_certificate.dump(camel_case)
-        if isinstance(self.auth_certificate, AuthCertificate):
+        if self.auth_certificate is not None:
             output["authCertificate" if camel_case else "auth_certificate"] = self.auth_certificate.dump(camel_case)
         return output
 
diff --git a/pyproject.toml b/pyproject.toml
index 8d065f95f2..45808d508b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,7 @@
 [tool.poetry]
 name = "cognite-sdk"
 
-version = "7.63.0"
+version = "7.63.1"
 description = "Cognite Python SDK"
 readme = "README.md"
 documentation = "https://cognite-sdk-python.readthedocs-hosted.com"
diff --git a/tests/tests_unit/test_data_classes/test_hosted_extractors/__init__.py b/tests/tests_unit/test_data_classes/test_hosted_extractors/__init__.py
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/tests/tests_unit/test_data_classes/test_hosted_extractors/test_jobs.py b/tests/tests_unit/test_data_classes/test_hosted_extractors/test_jobs.py
new file mode 100644
index 0000000000..864023bf3f
--- /dev/null
+++ b/tests/tests_unit/test_data_classes/test_hosted_extractors/test_jobs.py
@@ -0,0 +1,23 @@
+import yaml
+
+from cognite.client.data_classes.hosted_extractors.jobs import Job
+
+
+class TestJob:
+    def test_load_yaml_dump_unknown_config(self) -> None:
+        raw_yaml = """externalId: myJob
+sourceId: my_eventhub
+destinationId: EventHubTarget
+targetStatus: running
+status: running
+createdTime: 123
+lastUpdatedTime: 1234
+format:
+  type: value
+  encoding: utf16
+  compression: gzip
+config:
+  some: new_config
+  that: has not been seen before"""
+
+        assert Job.load(raw_yaml).dump() == yaml.safe_load(raw_yaml)