If the Creative Commons Attribution 4.0 is included in HTML used to create license, ArcGIS Open Data sites will go to the older version, Creative Commons 3.0, upon clicking on license in the ArcGIS Open Data dataset.
Remove the Creative Commons Attribution 4.0 from the HTML and it will open, <a href="http://creativecommons.org/licenses/by-nd/4.0/" target="_blank">http://creativecommons.org/licenses/by-nd/4.0/</a> which is the latest version.Correctly Working Example:Item Details:<a href="http://ess.maps.arcgis.com/home/item.html?id=1db6a9b282ac4a6082b6526b79186dc7" target="_blank">http://ess.maps.arcgis.com/home/item.html?id=1db6a9b282ac4a6082b6526b79186dc7</a> HTML: <a href="<a href="http://creativecommons.org/licenses/by/4.0/" target="_blank">http://creativecommons.org/licenses/by/4.0/</a>">International License</a>Open Data Dataset:<a href="http://markmullane.ess.opendata.arcgis.com/datasets/1db6a9b282ac4a6082b6526b79186dc7_0" target="_blank">http://markmullane.ess.opendata.arcgis.com/datasets/1db6a9b282ac4a6082b6526b79186dc7_0</a>