The alert came in at 04:11 in Cape Town, and for just a few minutes Thandi was the only person in her world who knew.
She wasn’t supposed to be awake. She had a script that watched the old addresses, the eleven hundred-odd wallets from 2009 everyone called the Patoshi set, and she’d set it to scream only for transfers over a single coin, because over the years there had been a hundred false alarms from people sending dust to the genesis address as a kind of prayer. The phone screamed. She looked at it the way you look at the kitchen smoke alarm you know not to trust, and then she sat up.
block 1,0xx,xxx · input: 1A1zP... no. input: 12c6DSiU... 50.00000000 BTC → bc1q... (new)
Fifty coins. Block 9, maybe, or close. The coinbase of a block mined when the whole network was a few computers and a mailing list.
She did the thing everyone does: she checked it on three explorers, as though the blockchain might disagree with itself. It didn’t. Then she did the thing only a few people did, which was check whether the transaction’s signature verified against a key nobody had seen used since January 2009. It did. Of course it did. It was in a block.
Her hands were completely steady. She noticed that with some interest.
By 04:20 the first bot posted it. By 04:24, there were sixty accounts posting it, and the price of bitcoin had fallen eleven percent on the Asian exchanges, not because anyone had sold, but because everyone knew everyone else was about to.
The argument started at 04:26. There were really only four possibilities, and the internet went through all of them in under an hour.
One: Satoshi was alive, and had decided, for reasons of their own, to move. A test, perhaps. Fifty coins out of a million was a sneeze.
Two: Satoshi was dead, and someone had found a hard drive. A widow. A nephew. A landfill in Newport.
Three: the key had been stolen, which would mean he had been careless, and nobody had ever thought he was careless.
Four, and this was the one Thandi’s stomach kept coming back to: someone had broken the cryptography. Not the hash, which would have been the end of everything, but the elliptic curve signature, which was the end of only the oldest coins, the ones whose public keys were sitting naked on the chain because in 2009 nobody had bothered to hide them.
If it was four, it would not be fifty coins. It would be all of them, in order, and the first one was just to see if anyone was watching.
At 05:02 she called Marcus, who ran the risk desk and was in London, where it was three in the morning, and who answered on the first ring because, he said, he had been awake since the first bot.
“Tell me it’s a widow,” he said.
“I can’t tell you anything. The coins moved. The signature’s good.”
“Customers?”
“Withdrawals are up nine times. Nothing’s broken. It’s just people.”
“It’s always just people,” Marcus said. “That’s what breaks.”
They ran the playbook. It was a real playbook, written two years earlier in a slightly embarrassed off-site where someone had asked “what if Satoshi sells?” and someone else had laughed and then nobody had laughed. Raise the margin requirements. Widen the circuit breakers. Write the customer message, the one that said we are monitoring and your funds are safe in the order that lawyers liked.
Thandi didn’t write the message. She opened the chain again.
The fifty coins had gone to a fresh address. That address had done nothing. It was just sitting there, like someone who had walked into a crowded room and then stood very still.
She looked at the transaction itself. Everyone was looking at the amount, but the amount was the least interesting thing about it. She looked at the fee, which was precise to the satoshi, the sort of round number a person types rather than the sort a wallet calculates. She looked at the version field, which was old. She looked at the output script, which was a modern one, the kind nobody in 2009 could have imagined.
And then she looked at the thing almost nobody looks at anymore, because it was a feature everyone had more or less forgotten: the transaction carried a tiny data output, a few dozen bytes with no value attached, that the network carries forever and never spends.
She decoded it. It took four seconds.
OP_RETURN: “Not a sale. A test of you, not of me. Look how fast you ran.”
By noon the price had come back. By the evening it was higher than it had been that morning, because the message had been screenshotted ten million times and the internet had decided, collectively and with no evidence at all, that it was the most bullish sentence ever written.
The exchange’s customer message went out at 06:15 and was immediately obsolete. The playbook was amended to include a new first step, which Marcus wrote himself and which read: Read the whole transaction.
Thandi went back to bed at seven and did not sleep. She lay there thinking about possibility four, which nobody was talking about anymore because the message had made everyone feel better. A man who could sign with that key could have written anything in that data field. So could someone who had broken the curve. A thief with a sense of humour and a long plan would write exactly that sentence, and then wait a year, and let everyone relax.
She got up, went to her laptop and changed the alert threshold on her script from one coin to zero.
Then she set it to call Marcus too.