In an ideal world the share values of the 2 companies should be equal but in practice this rarely happens - investors percetions change with the change in the company.  As for RSG they won't be 100% owners in the new company and may have limited control over that companies future. Until the new company has announced their management team and their objectives the value of the new (and the old) company will be a bit more difficult to assess. We can only hope for a swift splitting of the companies and new and positive priority statements from both. With a bit of luck both companies will continue to grow in value.