16 folder

• Current version: SharePoint Online Client Components from updated Nuget: http://www.nuget.org/packages/Microsoft.SharePointOnline.CSOM (version 16.1.3912.1204)
• Version until 10th of April 2015: SharePoint Online Client Components SDK: http://www.microsoft.com/en-us/download/details.aspx?id=42038 (version 16.0.3104.1200)
• Version up until September 3th 2014: SharePoint Online Client Components SDK: http://www.microsoft.com/en-us/download/details.aspx?id=42038 (version 16.0.2617.1200)

15 folder

• Current version: version deployed with the April 2015 CU: no separate redist (version 15.0.4711.1000)
• Version up until April 15th 2015: version deployed with the March 2015 CU: no separate redist (version 15.0.4701.1000)
• Version up until March 12th 2015: version deployed with the February 2015 CU: no separate redist (version 15.0.4693.1000)
• Version up until February 12th 2015: version deployed with the December 2014 CU: no separate redist (version 15.0.4675.1000)
• Version up until December 14th 2014: SharePoint Server 2013 Client Components SDK: http://www.microsoft.com/en-us/download/details.aspx?id=35585 (version 15.0.4641.1000). Note that only the following assemblies have been changed compared to the previous version:
• Microsoft.Online.SharePoint.Client.Tenant.dll
• Microsoft.SharePoint.Client.dll
• Version up until September 3th 2014: version deployed with the April 2014 CU: no separate redist (version 15.0.4605.1000)
• Up until version 2.0 of Office AMS (=old CodePlex release): SharePoint Server 2013 Client Components SDK: http://www.microsoft.com/en-us/download/details.aspx?id=35585 (version 15.0.4420.1017)