When you open a PDF file that conforms to PDF/A, PDF/E, PDF/X, or PDF/UA standard, the Standards panel icon automatically appears on the left side of the navigation pane, giving you a quick way to view the standards information of the PDF. You can choose View > Navigation Panels > Standards or click 
in the navigation panel to open the Standards panel. In the Standards panel, you will find the following information:
Conformance: shows the standard used to create the file, the ISO name, and whether the file has been verified as standard compliant. If the file has not been verified yet, you can click Verify Conformance in the Standards panel to start the conformance verification. If the verification fails, click Open Preflight under the standards information in the Standards panel to open the Preflight dialog box to run preflight inspections as needed. See also the Preflight dialog box.
OutputIntent: indicates the color settings associated with the file.