Gandi provides resellers with a free service that automatically accepts domain name transfers for you. This prevents you from having to click on a many emails to confirm domain transfers one at a time…

To activate this feature, begin by logging into your Gandi reseller handle. then:

1. click on the "Account" button on the top navigation menu,

2. click on "Configuration of my reseller options",

3. then, click "Incoming transfer management".

You will now be presented with a text that describes the service.

We provide you with a permanent authorization system to assist 
you in the transfer of multiple domains to your reseller account.

This permanent authorization function allows you to no longer be 
required to ask your customers to confirm the transfer by replying 
to the transfer confirmation e-mail.

After your e-mail address has been added via the form below, you 
will receive a confirmation e-mail that you must reply to within 
5 days. Once this has been confirmed, all transfer requests that 
have this e-mail address as the administrative contact will be 
automatically accepted. 

4. Check the box to accept, and add the email address that will be used for the automatic confirmation.

5. submit this to continue.

You will then be sent an email to the address provided that you must confirm within 5 days. It looks like this:

Subject of the mail: [GANDI] Request for Acceptance of Permanent Transfer

Dear Gandi customer,

You have just completed an online request for permanent transfer of 
all domains whose administrative contact is registered with the email:
example@example.com

In order to confirm the validity of this email address, we ask that you
confirm your request prior to 2011-03-15 12:03:47 by clicking on the
following link:
https://www.gandi.net/admin/reseller/foa/validate/820/3BWNfPjp

Reminder: Your handle is: ABC123-GANDI

6. click on the link in the mail to validate.

From then on, if that email address is listed as the email address in the whois for the domain name, it will automatically be confirmed when you request a transfer. All that remains is for you to accept in the name of the new owner (if applicable), or any special registry emails depending on the extension.