I set the reportSource parameters in Javascript and they get passed to the WebApi, but when the method my Report's ObjectDataSource is wired up to is called, the parameters are null. I setup the report parameters and the objectdatasource parameters and made sure they all have the same name. I have been used JustDecompile to see why the parameters don't get passed all the way through and it seems as though in the end the reportsource parameters are empty.