diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
index 55d20255..ff261bad 100644
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -3,7 +3,7 @@ FROM mcr.microsoft.com/vscode/devcontainers/python:0-${VARIANT}
 
 USER vscode
 
-RUN curl -sSf https://rye.astral.sh/get | RYE_VERSION="0.35.0" RYE_INSTALL_OPTION="--yes" bash
+RUN curl -sSf https://rye.astral.sh/get | RYE_VERSION="0.44.0" RYE_INSTALL_OPTION="--yes" bash
 ENV PATH=/home/vscode/.rye/shims:$PATH
 
 RUN echo "[[ -d .venv ]] && source .venv/bin/activate || export PATH=\$PATH" >> /home/vscode/.bashrc
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f2e55ba7..4f439a74 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -22,7 +22,7 @@ jobs:
           curl -sSf https://rye.astral.sh/get | bash
           echo "$HOME/.rye/shims" >> $GITHUB_PATH
         env:
-          RYE_VERSION: '0.35.0'
+          RYE_VERSION: '0.44.0'
           RYE_INSTALL_OPTION: '--yes'
 
       - name: Install dependencies
@@ -43,7 +43,7 @@ jobs:
           curl -sSf https://rye.astral.sh/get | bash
           echo "$HOME/.rye/shims" >> $GITHUB_PATH
         env:
-          RYE_VERSION: '0.35.0'
+          RYE_VERSION: '0.44.0'
           RYE_INSTALL_OPTION: '--yes'
       - name: Install dependencies
         run: |
diff --git a/.github/workflows/publish-pypi.yml b/.github/workflows/publish-pypi.yml
index 20e05af1..b7160d6a 100644
--- a/.github/workflows/publish-pypi.yml
+++ b/.github/workflows/publish-pypi.yml
@@ -21,7 +21,7 @@ jobs:
           curl -sSf https://rye.astral.sh/get | bash
           echo "$HOME/.rye/shims" >> $GITHUB_PATH
         env:
-          RYE_VERSION: '0.35.0'
+          RYE_VERSION: '0.44.0'
           RYE_INSTALL_OPTION: '--yes'
 
       - name: Publish to PyPI
diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 53079579..3da9036b 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.86.0"
+  ".": "0.86.1"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 60417917..0f3218b1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Changelog
 
+## 0.86.1 (2025-03-14)
+
+Full Changelog: [v0.86.0...v0.86.1](https://github.com/lithic-com/lithic-python/compare/v0.86.0...v0.86.1)
+
+### Bug Fixes
+
+* **types:** handle more discriminated union shapes ([#713](https://github.com/lithic-com/lithic-python/issues/713)) ([eb8c941](https://github.com/lithic-com/lithic-python/commit/eb8c941ab542757530dc5ec9ff1eba7a89aeac74))
+
+
+### Chores
+
+* **internal:** bump rye to 0.44.0 ([#712](https://github.com/lithic-com/lithic-python/issues/712)) ([0ac2afe](https://github.com/lithic-com/lithic-python/commit/0ac2afe1892ff69251a97e92cae24bcd1532598f))
+* **internal:** remove extra empty newlines ([#710](https://github.com/lithic-com/lithic-python/issues/710)) ([83aedda](https://github.com/lithic-com/lithic-python/commit/83aeddafa2aa3904f46017a026219d640a6c3da6))
+
 ## 0.86.0 (2025-03-12)
 
 Full Changelog: [v0.85.0...v0.86.0](https://github.com/lithic-com/lithic-python/compare/v0.85.0...v0.86.0)
diff --git a/pyproject.toml b/pyproject.toml
index c5463ad5..179a4943 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "lithic"
-version = "0.86.0"
+version = "0.86.1"
 description = "The official Python library for the lithic API"
 dynamic = ["readme"]
 license = "Apache-2.0"
@@ -38,7 +38,6 @@ Homepage = "https://github.com/lithic-com/lithic-python"
 Repository = "https://github.com/lithic-com/lithic-python"
 
 
-
 [tool.rye]
 managed = true
 # version pins are in requirements-dev.lock
diff --git a/requirements-dev.lock b/requirements-dev.lock
index 993d8d76..196ee452 100644
--- a/requirements-dev.lock
+++ b/requirements-dev.lock
@@ -7,6 +7,7 @@
 #   all-features: true
 #   with-sources: false
 #   generate-hashes: false
+#   universal: false
 
 -e file:.
 annotated-types==0.6.0
diff --git a/requirements.lock b/requirements.lock
index 49dcac95..0745afc3 100644
--- a/requirements.lock
+++ b/requirements.lock
@@ -7,6 +7,7 @@
 #   all-features: true
 #   with-sources: false
 #   generate-hashes: false
+#   universal: false
 
 -e file:.
 annotated-types==0.6.0
diff --git a/src/lithic/_models.py b/src/lithic/_models.py
index c4401ff8..b51a1bf5 100644
--- a/src/lithic/_models.py
+++ b/src/lithic/_models.py
@@ -65,7 +65,7 @@
 from ._constants import RAW_RESPONSE_HEADER
 
 if TYPE_CHECKING:
-    from pydantic_core.core_schema import ModelField, LiteralSchema, ModelFieldsSchema
+    from pydantic_core.core_schema import ModelField, ModelSchema, LiteralSchema, ModelFieldsSchema
 
 __all__ = ["BaseModel", "GenericModel"]
 
@@ -646,15 +646,18 @@ def _build_discriminated_union_meta(*, union: type, meta_annotations: tuple[Any,
 
 def _extract_field_schema_pv2(model: type[BaseModel], field_name: str) -> ModelField | None:
     schema = model.__pydantic_core_schema__
+    if schema["type"] == "definitions":
+        schema = schema["schema"]
+
     if schema["type"] != "model":
         return None
 
+    schema = cast("ModelSchema", schema)
     fields_schema = schema["schema"]
     if fields_schema["type"] != "model-fields":
         return None
 
     fields_schema = cast("ModelFieldsSchema", fields_schema)
-
     field = fields_schema["fields"].get(field_name)
     if not field:
         return None
diff --git a/src/lithic/_version.py b/src/lithic/_version.py
index d38424d2..573ad699 100644
--- a/src/lithic/_version.py
+++ b/src/lithic/_version.py
@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "lithic"
-__version__ = "0.86.0"  # x-release-please-version
+__version__ = "0.86.1"  # x-release-please-version
diff --git a/tests/test_models.py b/tests/test_models.py
index fe2eadcb..154fc144 100644
--- a/tests/test_models.py
+++ b/tests/test_models.py
@@ -854,3 +854,35 @@ class Model(BaseModel):
     m = construct_type(value={"cls": "foo"}, type_=Model)
     assert isinstance(m, Model)
     assert isinstance(m.cls, str)
+
+
+def test_discriminated_union_case() -> None:
+    class A(BaseModel):
+        type: Literal["a"]
+
+        data: bool
+
+    class B(BaseModel):
+        type: Literal["b"]
+
+        data: List[Union[A, object]]
+
+    class ModelA(BaseModel):
+        type: Literal["modelA"]
+
+        data: int
+
+    class ModelB(BaseModel):
+        type: Literal["modelB"]
+
+        required: str
+
+        data: Union[A, B]
+
+    # when constructing ModelA | ModelB, value data doesn't match ModelB exactly - missing `required`
+    m = construct_type(
+        value={"type": "modelB", "data": {"type": "a", "data": True}},
+        type_=cast(Any, Annotated[Union[ModelA, ModelB], PropertyInfo(discriminator="type")]),
+    )
+
+    assert isinstance(m, ModelB)