This layer participates in a geodatabase topology and cannot be edited with an ArcGIS for Desktop Basic license.
Solution: Upgrade your license to ArcGIS for Desktop Standard or ArcGIS for Desktop Advanced.
More information: A geodatabase topology requires an ArcGIS for Desktop Standard or ArcGIS for Desktop Advanced license. However, you can build a simple map topology that allows you to edit coincident geometry with an ArcGIS for Desktop Basic license.
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