Password is required to open the document. In general, the icons indicate the following security states: The Security icon on the Navigation Bar shows the current security settings of the active PDF. If a document is not open in Revu, and it is not checked out/locked by another user, changes will be applied and saved to the document automatically (without opening the document in Revu). If a document is open in Revu, any changes resulting from the process will be made to the document, but the document will not be saved or checked in (if relevant) the user will need to save and check in the document manually. PDFs do not need to be open in Revu when the process is run. This process can be performed on multiple PDFs at the same time. Some actions, such as certifying or digitally signing a document, automatically secure it. Some functions, such as splitting the document or extracting pages, cannot be performed without first breaking its security and doing so will revert the PDF to an unsecured state. Security can be set to restrict access to the PDF or to require a password for modification.