Only if that money is the proceeds of a crime and you're attempting to conceal the source of the illegal funds.
The flippant and universalizing way several of the commenters here are referring to money laundering as "concealing where the money came from" cast far too wide a net.
The definition you're using here would include concealing where $500 came from that was donated by anonymous friends to give to another friend in need. Suddenly, by your metric, if any of the friends suspected of donating the cash to help someone don't fess up to the source of the cash, they're laundering money.
Yeah, that's ridiculous. But it fits your description. Money laundering requires the currency be earnings from criminal activity.
If you're running a coin mixing service that makes the coins anonymous to others then as soon as a single transaction is true money laundering (from criminal activity), then you're liable for that. If a single Fed sting operation on silkroad buys drugs for some bitcoin that afterwards gets to your service - you're going down.
Pretty much the only way to do so 'properly' would require you to make the coins anonymous to the public, but ID all of your customers and keep records on who actually gets which coins in the end.
Like the other commenter, you're speaking to a different angle. I was commenting strictly on the repeated blanket statements made throughout these comments that any concealing of the source of money == money laundering. I was not speaking to liability ramifications of running a coin mixing service at all. I wasn't even contending that there might not be legitimate claims made against bitcoin activity that could be money laundering. The act of concealing where money came from as a general principle is not itself money laundering. Yes, running a service that facilitates concealing the source of money can quickly become a target and risk liability for laundering activities. That is still, however, an entirely different point.
Put your money where your mouth is. Openly run a mixer. Openly advertise that you are the person who operates it.
If you're right and I'm wrong, it'll be a lucrative business and you'll probably quickly dominate the mixer industry, as it'd be very easy for you to get press and build name recognition. You could do it as a very part-time job.
If I'm right and you're wrong, you'll be in prison.
The flippant and universalizing way several of the commenters here are referring to money laundering as "concealing where the money came from" cast far too wide a net.
The definition you're using here would include concealing where $500 came from that was donated by anonymous friends to give to another friend in need. Suddenly, by your metric, if any of the friends suspected of donating the cash to help someone don't fess up to the source of the cash, they're laundering money.
Yeah, that's ridiculous. But it fits your description. Money laundering requires the currency be earnings from criminal activity.