Information Rights Management (IRM) is a way to provide privacy protection for a Microsoft Office document and to ensure that sensitive information is only viewed by appropriate people. For example, you may want to report quarterly financial data only to select members of an executive committee one month before the data becomes publicly available in a financial statement, so they have time to prepare public relation responses and make appropriate business decisions.

Windows SharePoint Services Version 3.0 or later supports IRM on a document library and all the documents in that library (whether or not those individual documents are enabled with IRM). Once the document is uploaded to a document library enabled with IRM, the document, in effect, becomes IRM-enabled.

Excel Services does not support loading Excel workbooks that have been enabled with IRM, and it does not load an Excel workbook if it is enabled with IRM or comes from a document library enabled with IRM. However, if you want to take advantage of IRM, you can load an Excel workbook without IRM into Excel Services, open the workbook as a snapshot, and then save the snapshot to a document library that is enabled with IRM.