+another

The coins are already tainted.  The choice is whether or not to make it easier to see.  Right now, it's very difficult.  I don't see a problem with making it easier.  For example, I support the second amendment, because when everyone has a gun, the bad guys worry more about getting shot and therefore do less damage.  The "taint" is really up to the user anyway, programmatically based on the threshold which I originally misrepresented in the worst way, but also in real time when they see how many transactions have passed between the thief's address and their counterparty's.

This helps me understand you better.  Your goal is to avoid inconveniencing anyone who may have received stolen coin.  This is a goal I agree with.  It is already possible for any user receiving it to inconvenience the sender, and my proposal makes it easier, but doesn't require it.  I think I can go further toward agreeing with you by suggesting that one choose not to inconvenience a sender of "tainted" coin unless the tainted coin comes from a victim who has offered a reward - and even then, it's better to invite the sender to participate in the back-tracking rather than refuse to honor the transaction.

Oh you did win brownie points.  Your concern for the "hapless" middleman is something I should have considered in my original proposal.

If the +1s don't have the same objection (inconveniencing the hapless middlemen), I'd appreciate more explanation from you.

If you do try that then you are not an honest user.

If you say "this item costs 3BTC from any address except 1blehkljf or 1crapjkfd or 1pointlessjkfs5lkj or 1lamejkeil3q or..." then you are nuts but not dishonest I guess.

Oh dooglas, I've been meaning to tell you, your last deposit to Seals was rejected. About 6 steps back some mybitcoin coins got mixed in. So yeah.. please resend your deposit.

Since this is serious business I'm not going to assume anything. I'M TOTALLY KIDDING. WE'LL NEVER DO THAT.

In other words, when you look at the previous addresses through which the coin(s) came to you, it would make sense for the blacklist to stop when it hits a MtGox address.  So getting your BC from MtGox or another another assumed-reputable - let's say "whitelisted" - address prevents the report from showing it as tainted.  It's a good argument for having a whitelist too.

The fact that coin passed through an MtGox account in the past gives MtGox some ability to earn any reward offered by victims, but I haven't found any reward offered by victims.  Has anyone?

If you found out that a chain of transactions that didn't include any MtGox (or other well-known) addresses preceded your receipt of bitcoin started with one of the addresses used in a heist and the victim of that heist was offering rewards, would you just ignore it, talk to your counterparty, or report it to get a reward?  Would the size of the reward matter?

What the hell are you talking about?

Why not just keep the whole thing and call it your reward if you are a thief?

To break it down one more time.

Person A steals and buys candy from Person B who buys sex toys from Person C who tips Stripper D who deposits the money with you (lucky girl). Now you notice that once upon a time someone reported a theft so you confiscate the girl's money and get your reward. (I bet you'll want to subscribe to the service that accepts all reports and offers fat rewards, eh!?)

Probably Stripper D, now learning about the various taint reporting sites, goes and reports the same coins to have been stolen by you. But it's not all bad maybe the coins will find their way back to you again and you can claim that reward too.

You could try doing a third party thing. But then everyone would have a reason to mix their money into Mt Gox every now and then.

yet another +1

Because you don't yet understand this is a bad idea dscotese

yeah more like "disempowering bitcoin users".

Want to see empowering honest users? 

The power of escrow and a diligent buyer:
https://bt.irlbtc.com/view/85207