What Is the Genesis Block in Bitcoin Terms?

On Jan. 3, 2009, an anonymous developer or group calling themselves Satoshi Nakamoto made history when they released the Genesis Block, the original block containing the first 50 bitcoins, onto Sourceforge. Unlike any of the hundreds of thousands of blocks that came after, Nakamoto left a message in the code of the block:

"The Times 03/Jan/2009 Chancellor on brink of second bailout for banks"

That line comes straight from the headline of a London Times article dated Jan. 3, 2009, which detailed banks being bailed out by the British government. While Nakamoto never clearly stated the message's meaning, many have interpreted it as a reference to why Nakamoto developed Bitcoin: to cut out the banks and intermediaries viewed as corrupt and unreliable, electing to create a more people-driven currency.

The origin of the Genesis Block is shrouded in mystery—who is Nakamoto, why the bitcoins within the original block remain unspendable, why the subsequent block took five (or six) days to mine, and why people still transfer bitcoins into the Genesis Block.

Let There Be Bitcoin!

The Genesis Block, also known as Block 0, is the ancestor that every other Bitcoin block can trace its lineage back to since every block traces back to a past one. Nakamoto mined the original block on a CPU (as opposed to the specialized machines miners now need) without any competition since no one even knew it existed at the time. It wasn't even worth anything—at least in fiat terms. Back then, Bitcoin was more of an experiment than anything, and it would still take around a year before it started to catch on. It would be incredibly easy for current miners to solve these blocks, which were set at difficulty 1, a far cry from the current Bitcoin difficulty.

The next block, Block 1, wasn't mined until five days later, on Jan. 8. This is considered odd, as the average timestamp gap between blocks is about 10 minutes. There are a few theories regarding the delay: Some believe that there were actually six days between blocks to test out the Bitcoin system in order to make sure it was stable (with a backdated timestamp). More spiritual followers believe in the six days as an intent to recreate the story of God's rest after creating the world in six days.

In Honor of Satoshi 

While the original Genesis Block contained 50 bitcoins, people have been sending the address bitcoins in tribute to Nakamoto since the early days of the system. These donations and tips take on an even more symbolic meaning as it's quite possible that they are unable to be spent when they join the original address. It's unknown if Nakamoto's intent was to not let the 50 bitcoins in the original block be spendable or if it was an oversight, but the Genesis Block has become synonymous with Nakamoto and exists as both the backbone of the entire project and as a kind of shrine for fans of Nakamoto to throw their bitcoins into, kind of like a wishing well.

The Genesis Block remains, for many Bitcoin devotees, the key to identifying Nakamoto. The idea is that only Nakamoto would be able to use the private key associated with the block and other early blocks to sign a message. If someone was able to sign messages using the private keys of the original blocks, it would offer solid evidence that they are Nakamoto.

A Benevolent God

Nakamoto mined bitcoins for a few years after creating the Genesis Block because there was little competition. It is believed by the community, fans, and researchers that Nakamoto is the largest bitcoin holder, with an estimate of about 1 million bitcoins. Nakamoto hasn't moved any coins since disappearing entirely in 2011, and has never made any effort to cash out even before disappearing.

Nakamoto's disappearance is generally a calming absence for Bitcoin miners, because if they ever decided to return, it could wreak havoc on the entire infrastructure. Basically, should Nakamoto ever have the whim, they could flood the market with one million bitcoins, essentially annihilating the cryptocurrency's worth by introducing so much of it into the system. One bitcoin would become significantly less rare and thus worth far less.

The Bottom Line

The Genesis Block is the first block on a blockchain, but in the Bitcoin network, it is the first address of the entity that started it all, Satoshi Nakamoto. Perhaps the extra bitcoin offerings found in the Genesis Block are meant as a quasi-religious sacrifice or perhaps as a small "thank you" to the anonymous creator.

Either way, Nakamoto casts a long shadow over the creation, and as Bitcoin climbs further into the mainstream, more and more attention is given to the hints left in the Genesis Block.