Add a timestamp to signatures

You can include the date and time you signed the document as part of your signature. Timestamps are easier to verify when they’re associated with a timestamp authority’s trusted certificate. Including a timestamp helps to establish exactly when you signed the document and reduces the chances of an invalid signature. You can obtain a timestamp from a third-party timestamp authority or from the certificate authority that issued your digital ID.

Timestamps appear in the signature field and in the Signature Properties dialog box. If a timestamp server is configured, that timestamp appears in the Date/Time tab of the Signature Properties dialog box. If no timestamp server is configured, the signatures field displays the local time of the computer at the moment of signing.

Note: If you did not embed a timestamp when you signed the document, you can add one later to your signature. (See Establish long-term signature validation.) A timestamp applied after signing a document uses the time provided by the timestamp server.

Configure a timestamp server

To configure a timestamp server, you need the server name and URL, a Forms Data Format (FDF) file that contains the server settings, or a security settings file that contains the timestamp server information.

If you have a security settings file, install it and don’t use the following instructions for configuring a server. Make sure that you obtained the security settings file from a source that you trust. Don’t install it without checking with your system administration or IT department.

  1. Do one of the following:

    • In Acrobat, choose Advanced > Security Settings.

    • In Reader, choose Document > Security Settings.

  2. Select Time Stamp Servers on the left.
  3. Do one of the following:

    • If you have an FDF file with the timestamp server settings, click the Import button . Select the FDF file, and click Open.

    • If you have a URL for the timestamp server, click the New button . Type a name, and then type the server URL. Specify whether the server requires a user name and password, and then click OK.

Set a timestamp server as the default

If you have two or more timestamp servers configured, you can set one of them as the default.

Note: Before you set a timestamp server as the default, you may want to check if the timestamp authorities charge a usage fee.
  1. Do one of the following:

    • In Acrobat, choose Advanced > Security Settings.

    • In Reader, choose Document > Security Settings.

  2. Select the timestamp server, and click the Set Default button .
  3. Click OK to confirm your selection.