Bitcoin Private Post Jan 2019 Hard Fork Summary


The Bitcoin Private January 2019 hard fork occurred at block 455500 (~5 am EST) on Jan 5, 2019. We are happy to announce the hard fork was successful and would like to summarize the results.

1) At the time of Coinmetrics’ report, around 20.84 million coins were in the transparent pool. At block 455499 (pre-fork), ~20.85 million coins were in the transparent pool. At block 455500 (post-fork), ~20.85 million coins were in the transparent pool, suggesting that the bad actor did not deshield the illegitimate coins. Below are images showing the results of gettxoutsetinfo which show our evidence:

2) The amount of coins that should be in existence is approximately 20.64 million, meaning that only 210k illegimitate coins are likely in existence, rather than the 2.04 million originally created.

3) Coinmetrics’ originally suggested 300k illegitimate coins had been deshielded, however, our own analysis suggests this is actually 210k coins based on the facts in point 2 above.

4) It is now safe to use shielded addresses again.

What can we do about the 210k illegitimate coins?

Unfortunately, we have to assume these coins were traded on the market and therefore, any attempt to remove them would only hurt community members and likely not affect the bad actor. However, we are open to suggestions from the community on a path forward.

When is the removal of unmoved coins?

This will occur at block height 480000, which is likely around Feb. 16, slightly before when we originally suggested it would be in the white paper. Of course, this date could change slightly, so we will be monitoring the situation moving forward and keeping the community informed. We also intend to remind the community weekly via tweets that they should move their coins to a new address.

When will the fund be created to help those who lost legitimately shielded coins?

We plan on performing another hard fork after the removal of unmoved coins to change the block reward/halving schedule to a more reasonable schedule for a max of 21 million coins total. We are also thinking of instituting an algorithm change at this time. As far as the fund is concerned, this will be the best time for it’s creation and at the current moment, the BTCP Decentralized Marketing Team is winning the vote to manage this relief fund. The code for this is already being worked on, though it will have to be tweaked following the unmoved coin removal.

Who has supported the hard fork?

In terms of exchanges, we know with certainty that Nanex has upgraded their node. We know that TradeSatoshi and HitBTC have put their wallets into maintenance mode as well. We are awaiting updates from other exchanges. All major mining pools have upgraded their nodes, meaning that nearly 100% of the hashrate on Bitcoin Private is with the new chain. Furthermore, the contribution team has upgraded all of it’s infrastructure and the major third party wallets have also upgraded their nodes.

Will a Mac full node wallet be available soon?

Apple seems to have changed their compiler on Mojave in a way that makes the compiling of the source code fail. We are working on a solution to this issue and hope to have the binaries compiled soon.

How can a third party verify the results of the hard fork?

We encourage all community members to verify the results of the hard fork on their own.

If you would like to verify that no coins were deshielded just prior to the fork, you can compile a new node at 0% sync with the command “stopatheight=X” where you would like the daemon to stop running at the specified blockheight. After it stops, run it with the command connect=0 so that it cannot continue to sync and use the command btcp-cli.exe gettxoutsetinfo to see the total amount of transparent coins. You can repeat this process for any blockheight. NOTE: The “StopAtHeight” command was just added to the official daemon as of Jan 8th, 2019. Please compile on Linux if you wish to utilize it. Source code is here.

If you would like to verify that shielded coins prior to the fork are burned, the easiest way is if you had a small amount of BTCP in a shielded address, they should now be gone. If you did not have coins in a shielded address, you can follow the instructions by ch4ot1c here to run regtest and simulate the fork.

We would like to offer a special thank you to our community for sticking with BTCP through these tough times. We hope that our quick responses to these situations has helped to create confidence in our team.



Bitcoin & ZClassic fork-merge with a focus on making private cryptocurrency transactions mainstream.

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Bitcoin Private

Bitcoin & ZClassic fork-merge with a focus on making private cryptocurrency transactions mainstream.