You can initiate the transfer of claims to another law firm by using the Transfer Claims tool, available on the homepage under My Application Tools.

This tool is available to all Law Firm Administrators by default; access to this tool can be given to other user accounts by checking the Transfer Claim box when configuring their accounts using the Account Management tool.
 
The transfer will be completed once the substituting counsel accepts the claim(s) using the same tool. Detailed instructions can be found in the document below.