Does the creator of Bitcoin hold a 'master' private key?

Question

If the creator of Bitcoin was the one that started the blockchain and with every cryptographic operation deriving from that initial key, would the network be under the complete control of the creator?

The only way I could see this not being the case if the key was disseminated into the network, but I am unsure if that is the case.

If the key is control over the block-chain and if the key generator still holds the key, then regardless of the fact that it is decentralized in operation, it is still centralized in control, like a bank.

I guess I'm really asking whether the creator had/has any advantage in the network (i.e reversing transactions, creating new coins, etc). Unless he specifically programmed the network not to be under his control, it would be right? I mean he IS the creator of the network and unless we have proof (source code inspection?) that the network has been 'turned over' so to speak to the users, we cannot guarantee safety can we?

Answer 1

No one holds a key that gives them special control of the blockchain.

The closest thing to a "master key" was the alerts system, which allowed signed messages to be sent to every client, for example, to tell users to update their client in response to a security issue. This feature was for alerts only and can in no way affect the blockchain, transactions, or user balances. This key was possessed by Satoshi, Gavin Andresen, and theymos.

Update: The alerts system was retired in the summer of 2018, due to risk of DOS attack vectors (full nodes could be DOS attacked by carefully crafted alert messages), and increasingly widespread knowledge of the alert keys.

Answer 2

Satoshi likely has the key corresponding to the address the coinbase of the genesis block was sent to. This is no different then any subsidy (mining income) produced by any later block. It does not grant any special privileges beyond that.

Actually, not even that, as because of either a bug or a conscious choice, the output of the genesis block cannot be spent.

Answer 3

Remember, the bitcoin protocol and the code for most clients is open source. You can check it yourself.

If there was a "master key", then we would know. It's very hard to hide such things in code when it will be reviewed by tons of others. (Yes, hiding malicious code can be done, but not at this level).

However, note that Satoshi and a few others have access to update your client. What would happen if they pushed a malicious update? Simple: the community would notice. They would spread the news, and a new blockchain would be branched from the last block created before the malicious update.

Answer 4

Similar to how terrible laws get passed during a crisis (e.g., the Federal Reserve's passage on Christmas eve, or after journalists call it a night on Friday), there is the potential risk that developers would release software during a crisis in which proper vetting hasn't occurred.

But most of the major players build the Bitcoin-Qt/bitcoind from source and can evaluate changes themselves. For instance, Slush pool used an emergency fix shared by a member of the Bitcoin-Qt/bitcoind core development team to cause the v0.8 client to ignore the offending block following the March 11th, 2013 hard fork emergency. The patch involved a few lines of source code changes that could be shared via any method, including a direct personal message.

If instead that change happened to be quite large, the risk of not recognizing code that is malicious increases. For this reason, if either the complexity or urgency of an informal fix grows, the resistance to implement it until a formal release arrives should increase. Formal releases are signed by the Bitcoin Foundation and are distributed through normal channels (and not passed as patches directly from developers to miners.)