This topic describes what's new for ASP.NET Web API OData 5.3.
- [Download](#download)
- [Documentation](#documentation)
- [OData Core Libraries](#corelib)
- [New Features](#newf)
- [Known Issues and Breaking Changes](#known-issues)
- [Bug Fixes](#bug-fixes)
- [ASP.NET Web API OData 5.3.1](#OD)
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## Download
The runtime features are released as NuGet packages on the NuGet gallery. You can install or update to the released NuGet packages by using the NuGet Package Manager Console:
An *open type* is a stuctured type that contains dynamic properties, in addition to any properties that are declared in the type definition. Open types let you add flexibility to your data models. For more information, see xxxx.
### Support for dynamic collection properties in open types
Previously, a dynamic property had to be a single value. In 5.3, dynamic properties can have collection values. For example, in the following JSON payload, the `Emails` property is a dynamic property and is of collection of string type:
For more information, see [OData Complex Type Inheritance Sample](http://aspnet.codeplex.com/SourceControl/latest#Samples/WebApi/OData/v4/ODataComplexTypeInheritanceSample/ReadMe.txt).
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## Known Issues and Breaking Changes
This section describes known issues and breaking changes in the ASP.NET Web API OData 5.3.
### OData v4
#### Query Options
Issue: Using nested $expand with $levels=max results in an incorrect expansion depth.
In this release we made a [bug fix](https://aspnetwebstack.codeplex.com/workitem/list/advanced?keyword=&status=All&type=All&priority=All&release=v5.3.1%20Beta&assignedTo=All&component=Web%20API%20OData&sortField=LastUpdatedDate&sortDirection=Descending&page=0&reasonClosed=All) to some of the AllowedFunctions enums. This release doesn't have any other bug fixes or new features.