With Lync 2013 and Exchange 2013, you can choose to archive Instant Messaging and web conferencing transcripts into the user's mailbox rather than doing it into a SQL database configured for the Lync archiving role.
The data will be archived in a hidden folder called
Purges within the user's mailbox. The
Purges folder is under the recoverable items folder in the mailbox of the user. You could then perform an eDiscovery search in the user's mailbox to find those items, if required. You need to be aware that the Lync data archived requires storage on Exchange and, therefore, needs to be taken into account when designing the Exchange 2013 Servers, especially when calculating the storage space. ...