Two people from the Board and one person not from the Board: A{2}+(B|C|D)

One person from the Board, and two people not from the Board but from two different groups: A+(B|C|D){2}

Three people not from the Board but from three different groups: (B+C+D){3}

N shares, one for each person from the Board

People from the Board know the composition of each group

People not from the Board:

Are explained in which circumstances they should revoke the signing key

Are told to write to a certain contact email address if they decide to revoke the signing key

Are told that they need three different shares to reassemble the revocation certificate

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Subject: distribution

We want to propose you to be part of a distributed mechanism for the revocation certificate of the Tails signing key.

Note: In all this document, 'us' refers to the Board.

How to store your share

Please keep your share in an encrypted storage and make it as hard as you can for untrusted people to get a copy of it.

You can rename the file as long as you keep the number in the file name of your share as it is needed to use the share.

Feel free to back up the file but we might also request you to delete it at some point and you should be able to know whether you still have a copy of it or not. It is all-right to lose your share as long as you tell us that you have lost it. It is actually worse to still have a copy of the share "somewhere" while thinking that you don't, than to lose it by mistake.

Don't hesitate to ask us if you need clarification on the technical aspects of this.

When to use your share

Everybody in possession of a share is subscribed to a mailing list.

If someone in possession of a share gets to learn about a very bad event that happened to many of us and really thinks that we are not capable of revoking the Tails signing key ourselves anymore, then this person should write to the mailing list explaining why she thinks that the signing key needs to be revoked.