Track modifications made to data
You can view the versions for each individual contact, portfolio, transaction, trade order, security, market price information or transaction type setting from the Versions button in the corresponding window: the Versions window shows the newest 50 versions with the time of the version, the user who has made the changes and the type of the change.
Version button is a question mark, and it is located in the bottom of the page.
For more information, see Track data modifications through versions in FA Back reference.