Many Bitcoin users have been reporting mysterious 1 satoshi (0.00000001BTC) transactions being sent to their wallets. The transactions are being sent from vanity Bitcoin addresses beginning with "1Enjoy" and "1Sochi," and theories behind the transactions range from it being a new kind of spam, to an attempt to bloat the blockchain, to an effort to attack Bitcoin addresses to people, to it merely being a test.

The earliest reference to such transactions I've been able to find date back to October, 2013, but there has been a sharp escalation in the last several days. I've personally received a score or more of them, including these three recent transactions to a wallet on Blockchain.info:

Three 1 Satoshi Transactions - Unconfirmed

There are three addresses sending me these transactions:

Note that all three transactions are unconfirmed. This means that the blockchain (i.e. Bitcoin miners) are ignoring these transactions. This is because of their size—0.00000001BTC, which is worth US$0.0000066211. That's a little more than 6/10,000 of a penny, or dust, as it's called.

Currently, the minimum transaction that is likely to get confirmed is 5,430 satoshis, or 0.0000543BTC, more than 5,000 times this useless dust, and that doesn't include the transaction fee. That's why many of the Bitcoin faucets I've been testing have minimum cashouts of 5800 satoshis or more.

What I've experienced, and what many other Bitcoin users on various forums have reported is that these transactions "fail" after a few days and disappear from your wallet. The question is, however, why were they sent in the first place?

We don't know the answer to that question, but there are several theories.

Spam

The first theory is that these transactions are intended as spam. This goes back to some of the earliest reports, where the Bitcoin address used to send the satoshi traced back to one gambling site or another. The thought is that the spammers are counting on some recipients being gamblers who will then follow the trail, discover a gambling site, and deposit Bitcoins on that site.

That's pretty reasonable for addresses that trace back to a known site. It's essentially free advertising because the transactions will never go through and the spammers get their Bitcoins back.

Thought of in another way, one Bitcoin—worth $662.11 as of this writing—can send out 1 million of these transactions. If 1 percent of them went through (they wouldn't), that would cost the spammers $6 and change, on par with email spam.

The problem is that this theory only covers transactions that trace back to a known site, service, or something, anything, identifiable. In the case of the three address above, what exactly are they spamming? The Sochi Olympics? Is it Coca Cola with a super stealth campaign to Enjoy [Coke]? I doubt either, to say the least.

Bloat Attack

Another theory is that this is an attempt to bloat the blockchain and slow down the network. If so, it's a terrible idea, at least on the scale that it is being done now. The network can handle these transactions, and in fact, it largely ignores them.

Who Are You?

A far more intriguing idea is that these transactions are designed to map out who owns what address. Think NSA, CIA, that hacking team run by the Chinese military, or whatever the heck the Russians are doing these days.

Under this scenario, nerdspooks harvest addresses from the blockchain (remember that any address that has received Bitcoin is known publicly on the blockchain), send out these transactions and then look to see who complains about it on BitcoinTalk.org, reddit, or this very site.

Those who include their address in their comment/post/complaint will then be outed, and MUHAHAHA! A tiny corner of the map gets filled in. It's a fiendish plan that might have been designed by this guy:

It's nonsense, and I don't buy it.

Testing, Testing, 1, 2, 3

The theory that I like the most is that we're seeing some kind of test from either a commercial spamming organization or one of the world's intelligence organizations. I have no idea what exactly is being tested, but in that no other idea makes any sense, I'll settle for this one.

Should You Worry?

It's important to note that receiving one of these transactions means little or nothing. There is nothing that he sender can get from you, including information, by sending you a satoshi. As noted above, every Bitcoin wallet address that has ever received (or sent) Bitcoins is already publicly known, and they had to already have harvested even that from the blockchain before they sent you the satoshi.

That's part of the point of Bitcoin. The anonymity of the cryptocurrency comes from the fact that while the transactions are public, the owners of an address are not.

The reality is that the transaction will simply go away, and there is no discernible threat in receiving one. I spoke to a pool operator about this, and he was utterly unconcerned about this issue. I recommend the same attitude for normal users, too.

Dust-b-gone

There was a clever piece of open source software released in December called dust-b-gone. As of this writing, it's Windows only, but what it does is collect all the dust out of a Bitcoin-QT wallet (a client-side wallet), and then bundle them into one transaction that is essentially sent to miners in the form of transaction fees.

That serves the handy purpose of keeping the spammers/attackers/testers from getting their Bitcoins back, while rewarding the miners who process all of the transactions.

I don't run a wallet on Windows, or I'd try out dust-b-gone. If these transactions persist, I'm hoping a Mac developer ports the software or develops something similar for Mac users.

It would also be nice if online wallets like Blockchain.info or Coinbase developed a tool that allowed users to do something similar on server-side wallets.

Image made with help from Shutterstock.