diff --git a/api/tests/opentrons/protocol_runner/test_json_translator.py b/api/tests/opentrons/protocol_runner/test_json_translator.py
index 0c65274ad9a..6dbba6a006c 100644
--- a/api/tests/opentrons/protocol_runner/test_json_translator.py
+++ b/api/tests/opentrons/protocol_runner/test_json_translator.py
@@ -13,6 +13,10 @@
     Group,
     Metadata1,
     WellDefinition,
+    BoundedSection,
+    RectangularCrossSection,
+    InnerLabwareGeometry,
+    SphericalSegment,
 )
 from opentrons_shared_data.protocol.models import (
     protocol_schema_v6,
@@ -685,6 +689,31 @@ def _load_labware_definition_data() -> LabwareDefinition:
         },
         dimensions=Dimensions(yDimension=85.5, zDimension=100, xDimension=127.75),
         cornerOffsetFromSlot=CornerOffsetFromSlot(x=0, y=0, z=0),
+        innerWellGeometry=InnerLabwareGeometry(
+            frusta=[
+                BoundedSection(
+                    geometry=RectangularCrossSection(
+                        shape="rectangular",
+                        xDimension=7.6,
+                        yDimension=8.5,
+                    ),
+                    topHeight=45,
+                ),
+                BoundedSection(
+                    geometry=RectangularCrossSection(
+                        shape="rectangular",
+                        xDimension=5.6,
+                        yDimension=6.5,
+                    ),
+                    topHeight=20,
+                ),
+            ],
+            bottomShape=SphericalSegment(
+                shape="spherical",
+                radius_of_curvature=6,
+                depth=10,
+            ),
+        ),
         brand=BrandData(brand="foo"),
         metadata=Metadata(
             displayName="Foo 8 Well Plate 33uL",
diff --git a/shared-data/python/opentrons_shared_data/labware/labware_definition.py b/shared-data/python/opentrons_shared_data/labware/labware_definition.py
index 1b2e68040de..537ea89ee27 100644
--- a/shared-data/python/opentrons_shared_data/labware/labware_definition.py
+++ b/shared-data/python/opentrons_shared_data/labware/labware_definition.py
@@ -224,6 +224,55 @@ class Config:
     )
 
 
+class CircularCrossSection(BaseModel):
+    shape: Literal["circular"] = Field(..., description="Denote shape as circular")
+    diameter: _NonNegativeNumber = Field(
+        ..., description="The diameter of a circular cross section of a well"
+    )
+
+
+class RectangularCrossSection(BaseModel):
+    shape: Literal["rectangular"] = Field(
+        ..., description="Denote shape as rectangular"
+    )
+    xDimension: Optional[_NonNegativeNumber] = Field(
+        None,
+        description="x dimension of a subsection of wells",
+    )
+    yDimension: Optional[_NonNegativeNumber] = Field(
+        None,
+        description="y dimension of a subsection of wells",
+    )
+
+
+class SphericalSegment(BaseModel):
+    shape: Literal["spherical"] = Field(..., description="Denote shape as spherical")
+    radius_of_curvature: _NonNegativeNumber = Field(
+        ...,
+        description="radius of curvature of bottom subsection of wells",
+    )
+    depth: _NonNegativeNumber = Field(
+        ..., description="The depth of a spherical bottom of a well"
+    )
+
+
+TopCrossSection = Union[CircularCrossSection, RectangularCrossSection]
+BottomShape = Union[CircularCrossSection, RectangularCrossSection, SphericalSegment]
+
+
+class BoundedSection(BaseModel):
+    geometry: TopCrossSection = Field(
+        ...,
+        description="Geometrical information needed to calculate the volume of a subsection of a well",
+        discriminator="shape",
+    )
+    topHeight: _NonNegativeNumber = Field(
+        ...,
+        description="The height at the top of a bounded subsection of a well, relative to the bottom"
+        "of the well",
+    )
+
+
 class Metadata1(BaseModel):
     """
     Metadata specific to a grid of wells in a labware
@@ -252,6 +301,18 @@ class Group(BaseModel):
     )
 
 
+class InnerLabwareGeometry(BaseModel):
+    frusta: List[BoundedSection] = Field(
+        ...,
+        description="A list of all of the sections of the well that have a contiguous shape",
+    )
+    bottomShape: BottomShape = Field(
+        ...,
+        description="The shape at the bottom of the well: either a spherical segment or a cross-section",
+        discriminator="shape",
+    )
+
+
 class LabwareDefinition(BaseModel):
     schemaVersion: Literal[1, 2] = Field(
         ..., description="Which schema version a labware is using"
@@ -326,3 +387,7 @@ class LabwareDefinition(BaseModel):
         default_factory=None,
         description="Force, in Newtons, with which the gripper should grip the labware.",
     )
+    innerWellGeometry: Optional[InnerLabwareGeometry] = Field(
+        None,
+        description="A list of bounded sections describing the geometry of the inside of the wells.",
+    )
diff --git a/shared-data/python/opentrons_shared_data/labware/types.py b/shared-data/python/opentrons_shared_data/labware/types.py
index a938f337c0f..8a6135de8f9 100644
--- a/shared-data/python/opentrons_shared_data/labware/types.py
+++ b/shared-data/python/opentrons_shared_data/labware/types.py
@@ -3,7 +3,7 @@
 types in this file by and large require the use of typing_extensions.
 this module shouldn't be imported unless typing.TYPE_CHECKING is true.
 """
-from typing import Dict, List, NewType, Union
+from typing import Dict, List, NewType, Union, Optional
 from typing_extensions import Literal, TypedDict
 
 
@@ -37,6 +37,7 @@
 
 Circular = Literal["circular"]
 Rectangular = Literal["rectangular"]
+Spherical = Literal["spherical"]
 WellShape = Union[Circular, Rectangular]
 
 
@@ -117,6 +118,37 @@ class WellGroup(TypedDict, total=False):
     brand: LabwareBrandData
 
 
+class CircularCrossSection(TypedDict):
+    shape: Circular
+    diameter: float
+
+
+class RectangularCrossSection(TypedDict):
+    shape: Rectangular
+    xDimension: float
+    yDimension: float
+
+
+class SphericalSegment(TypedDict):
+    shape: Spherical
+    radius_of_curvature: float
+    depth: float
+
+
+TopCrossSection = Union[CircularCrossSection, RectangularCrossSection]
+BottomShape = Union[CircularCrossSection, RectangularCrossSection, SphericalSegment]
+
+
+class BoundedSection(TypedDict):
+    geometry: TopCrossSection
+    topHeight: float
+
+
+class InnerLabwareGeometry(TypedDict):
+    frusta: List[BoundedSection]
+    bottomShape: BottomShape
+
+
 class _RequiredLabwareDefinition(TypedDict):
     schemaVersion: Literal[2]
     version: int
@@ -138,3 +170,4 @@ class LabwareDefinition(_RequiredLabwareDefinition, total=False):
     gripperOffsets: Dict[str, GripperOffsets]
     gripForce: float
     gripHeightFromLabwareBottom: float
+    innerWellGeometry: Optional[InnerLabwareGeometry]