To enable or disable usage sharing in the 51Degrees .NET API you should look in your 51Degrees.config file within your web project. In this settings file there is a element titled detection containing detailed instructions about the available settings. One of these setting is the shareUsage property. So to enable or disable this feature, set this to true or false in the detection element. The line in your file should look like this:
<detection enabled="true" autoUpdate="true" binaryFilePath="~/App_Data/51Degrees.dat" shareUsage="true" />
The usage sharing URL is compiled into the DLL. However, should you need to change this, the setting can be found in "Properties/DetectionConstants.cs" within the FoundationV3 project.