The Create Bookmark Link is enabled by default in OBIEE. The following entry in the instanceconfig.xml under the "ServerInstance" node decides the feature of create bookmark link and create prompted link.
<Dashboard>
<EnableBookmarkURL>True</EnableBookmarkURL>
<EnablePromptedURL>True</EnablePromptedURL>
<BookmarkExpirationDays>30</BookmarkExpirationDays>
</Dashboard>