From the Dreamwidth FAQ
How do I invite someone to Dreamwidth?
To invite someone you need an Invite Code. You don't have to do anything to obtain these Invite Codes - from time to time, we'll create new Invite Codes and automatically distribute them among active Dreamwidth account holders.
Once you have an Invite Code, you can invite someone to join Dreamwidth Studios on the Invite Someone page. There you can type in their email address and - if you like - edit the welcome message we'll send to them.
The Invite Code system is designed to let Dreamwidth grow slowly and sustainably, but we don't want to keep out people who really want to start using Dreamwidth. If you need extra Invite Codes, let us know. We should be able to help.
I've requested codes, yet still haven't recieved any feedback from the DW team. It's been a while, too. I wonder what gives?
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