# ObserverManager<TIdentity, TObserver>.ClearExpired

[Type overview](/orleans/docs/api/csharp/microsoft.orleans.core/orleans.utilities.observermanager-2/) | [Methods](/orleans/docs/api/csharp/microsoft.orleans.core/orleans.utilities.observermanager-2/methods/)

[Source](https://github.com/dotnet/orleans/blob/e4e752cedecc2976811db49802c7a999b1f1c704/src/Orleans.Core/Utils/ObserverManager.cs#L251-L268)

```csharp
public void ObserverManager<TIdentity, ClearExpired()
```

Removed all expired observers.