Subject: Re: [Bitcoin-development] [BIP draft] CHECKLOCKTIMEVERIFY - Prevent a txout from being spent until an expiration time

From: Peter Todd <[email-masked]>
Date: Wed, 01 Oct 2014 17:12:51 -0700

On 1 October 2014 14:34:33 GMT-07:00, Gavin Andresen <[email-masked]> wrote:
>On Wed, Oct 1, 2014 at 5:04 PM, Alan Reiner <[email-masked]>
>wrote:
>No, the burner would supply the funding transaction plus the redeeming
>script as the proof-of-burn to whoever needed the proof.

No, the redeemScript has to be provably published to miners for the sacrifice to be valid; if not you can exploit the scheme by hiding the redeemScript and having a big miner mine it at lower-than-face-value cost when it unlocks.

>Only after at least one confirmation, if there was some risk that
>revealing
>the redeeming script would make miners refuse to mine that first
>transaction because they want to get it plus the CHECK TIME BLOCK VERIFY
>"burn"
>transaction.

Yes, you could do that in a followup tx containing the redeemScript in an OP_RETURN output to prove publication. That said as I said to Luke-Jr, the sacrifices need to unlock pretty far into the future, so I don't see miners bothering to do this.