# OwnerPropertyDef

Location: [gRPC API](https://developer.m-files.com/APIs/gRPC-API/index.md) > [Reference](https://developer.m-files.com/APIs/gRPC-API/Reference/index.md) > [Messages](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/index.md)

HTML version: https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.OwnerPropertyDef/

Struct for a single owner property definition.

- **Full name:** `MFiles.OwnerPropertyDef`
- **Proto file:** [`mfiles/structs.proto`](https://developer.m-files.com/APIs/gRPC-API/downloads/proto/mfiles/structs.proto)

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## Fields

| Field | Type | Number | Description |
|---|---|---|---|
| <a id="f-property_def"></a>`property_def` | `int32` | 1 | The ID of the owner property definition, or -106 if the owner property is determined automatically. |
| <a id="f-dependency_relation"></a>`dependency_relation` | [`DependencyRelation`](https://developer.m-files.com/APIs/gRPC-API/Reference/Enums/MFiles.DependencyRelation/index.md) | 2 | How this property depends on its owner property: `DEPENDENCY_RELATION_FILTER` limits its values to those that belong to the owner property's value, `DEPENDENCY_RELATION_FILL` fills it automatically from the owner property's value. Values: `DEPENDENCY_RELATION_NOTHING` (0), `DEPENDENCY_RELATION_FILL` (1), `DEPENDENCY_RELATION_FILTER` (2). |
| <a id="f-data"></a>`data` | [`DependentPropertyDefUnion`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.DependentPropertyDefUnion/index.md) | 3 | Details of the `DEPENDENCY_RELATION_FILL` relation. |

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## Used in fields

- [`PropertyDef.owner_property_def_info`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.PropertyDef/index.md#f-owner_property_def_info): For a lookup property, the property whose value limits this property's values. For example, Workflow State (39) is limited by Workflow (38). A `property_def` of -106 means that the owner property is determined automatically.