For example, bitmixer.io holds ~1000 BTC reserve for mixing, which is currently worth ~$2.5 million. So ~60 BTC could be safely mixed over a few days.
Decent mixers:
bitmixer.io (bitmixer2whesjgj.onion)
Bitcoin Fog (foggedddxlunnaaa.onion)
Helix (grams7enufi7jmdl.onion/helix/light)
I'm not aware that exchanges have blacklisted any mixers. There has been talk of blacklisting stolen Bitcoin, but I don't believe that's been done either.
DO NOT USE BitcoinFog
I've used them for years. They've been slow a few times, but I've never lost anything.
There are persistent hater threads on Bitcoin Forum, however. And they've gotten some bad PR from some major Bitcoin thefts. Also, the Sheep Marketplace owner did screw up by mixing 96000 BTC in one go. But that still wasn't how he got pwned.
If Bitcoin has evolved to the point where you need to have currency exchanges that act just like banks... what's the point?
The hackers can still spend the money on something else provided the other party doesn't hold themselves to the same standards.
It's also public record where transactions travel on the blockchain, so if it was ever noted what address the funds entered, I imagine it could prove difficult to dilute the transactions enough that the ledger wouldn't be accepted as proof. But I'm just speculating on that last bit.
you can trade bitcoin to bitcoin just fine
As a result, no online currency exchange will touch it, said Jake Williams, founder of Rendition Infosec, a cybersecurity firm. “This is like knowingly taking tainted bills from a bank robbery,” he said.
Could anyone give some more details about this?
Does a trustworthy bitcoin mixer exist? Would the attackers be able to use it to launder the coins?
EDIT: Does anyone know anything about the operational error mentioned in the article?
The coins are easy to track, but that's the default for bitcoin. Mixing the coins should restore anonymity in most cases, right? And at that point it would be possible to move the coins back to an exchange, or sell them on localbitcoins.
On the other hand, have the exchanges blacklisted most of the large mixers? It seems like it should be theoretically possible to track whether coins have been mixed. Then exchanges could simply close any account that receives significant sums of tumbled coins.