chainfork.html

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        <h1>11/12 March 2013 Chain Fork Information</h1>
        <h2>What happened</h2>
<p>
A bitcoin miner running version 0.8.0 created a large block (at height 225,430) that is incompatible
with earlier versions of Bitcoin.
</p>
<p>
The result was a block chain fork, with miners, merchants and users running the new version of bitcoin
accepting, and building on, that block, and miners, merchants and users running older versions of bitcoin
rejecting it and creating their own block chain.
</p>
        <h2>What is being done</h2>
<p>
Large mining pools running version 0.8.0 were asked to switch back to version 0.7, to create a
single block chain compatible with all bitcoin software.
</p>
        <h2>Questions &amp; Answers</h2>
<h3>I'm not a miner or a merchant, what should I do?</h3>
<p>
Nothing. Your bitcoin software will switch to the correct chain automatically, no matter
which version you are running.
</p>
<h3>Are my bitcoins safe?</h3>
<p>
Yes.
</p>
<h3>I'm a merchant accepting bitcoins, what should I do?</h3>
<p>
If you are running version 0.8.0, there is a small risk that payments with more than
6 confirmations could be double-spent on the 0.7-compatible blockchain. The risk is small
because this is not a network split-- transactions are being sent to both sides of the
chain split, and it is unlikely (but possible) that somebody could get two versions of the
same transaction into the two sides of the chain.
</p>
        <h2>What will be done</h2>
<p>
The core developers are investigating exactly what causes the old versions to reject the new
blocks, and will release a 0.8.1 version that avoids creating blocks that are incompatible with
older versions.
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         <i>This notice last updated: 12 March 2013 02:45 UTC</i>
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