Display enterprise themes
Supported on: At least Windows Server 2008 R2 or Windows 7
Registry
HKCU
software\policies\microsoft\office\16.0\powerpoint\options Options
themesgalleryshowcorporateonly boolean themesgallerycorporatesectiontitle text Description
This policy allows you to display enterprise themes in the ribbon galleries. You can also name the category for the themes, and you can hide all the Office in-box and connected gallery themes.