What sites exist to check if an address is involved in reported activity?

[kayrice]

Are there any sites that let a user give an address and check a database?

Edit: I should be clear I'm talking about something where you put the address in and it says like DANGER

[cst]

http://www.blockchain.info/
https://blockexplorer.com/

[kayrice]

Sorry, I should have been clear, I'm talking about something where you put the address in and it says like DANGER

[Sukrim]

Would be easy to do: Check if the data entered is a bitcoin address - if yes, display "DANGER!!!" (exclamation marks added for emphasis).

[kayrice]

I have an idea but no time to implement it currently. Basically you download the entire blockchain and analyze it like a graph. When a user queries the system to check for danger this would be free and give a "legitness" value showing the sum of BTC estimated to be in dispute. This would be weighted based on transactions with others that are disputed. Reviews would be entered by sending a small amount from the same address disputing the transaction which would also be used as a weighting factor. So if the person is disputing a 10 BTC transaction with a confidence of 2 BTC the other party would be seen as "20 BTC illegit". Anyone who received coins from him directly (possibly limited by time intervals) would have the -20 applied to their score scaled by an "interaction factor" from 0.0 - 1.0 of how much money received over time. So a money launderer would have a rating higher like 0.8 if 80% of their transactions just got piped to another account, even if there was a large volume of them in small amounts.

Thats my take on it. Would be cool to make. Maybe a github repo will start growing hair one day.

[cst]

I have an idea but no time to implement it currently. Basically you download the entire blockchain and analyze it like a graph. When a user queries the system to check for danger this would be free and give a "legitness" value showing the sum of BTC estimated to be in dispute. This would be weighted based on transactions with others that are disputed. Reviews would be entered by sending a small amount from the same address disputing the transaction which would also be used as a weighting factor. So if the person is disputing a 10 BTC transaction with a confidence of 2 BTC the other party would be seen as "20 BTC illegit". Anyone who received coins from him directly (possibly limited by time intervals) would have the -20 applied to their score scaled by an "interaction factor" from 0.0 - 1.0 of how much money received over time. So a money launderer would have a rating higher like 0.8 if 80% of their transactions just got piped to another account, even if there was a large volume of them in small amounts.

Thats my take on it. Would be cool to make. Maybe a github repo will start growing hair one day.

Sounds like address tainting? And considering that getting a new address takes only a couple clicks it's totally meaningless.

[kayrice]

And considering that getting a new address takes only a couple clicks it's totally meaningless.

You don't understand the math? Creating more edges in the graph would not help you since I would be modelling all the connections you made. Unless you are going to conduct every transaction with entirely separate addresses, never mixing any funds at all between yourself or mutual parties that aren't a laundering service designed to circumvent this, the amount of funds you've been exposed to that is disputed is modeled.

[rebuilder]

a laundering service designed to circumvent this

And why would anyone with "illegitimate" funds not use one?

[cst]

And considering that getting a new address takes only a couple clicks it's totally meaningless.

...
Unless you are going to conduct every transaction with entirely separate addresses, never mixing any funds at all between yourself or mutual parties that aren't a laundering service designed to circumvent this
..

That's exactly what I would be doing.

[kayrice]

I suppose it could have an "unknown" state for people who have never made any transactions. But let's assume you generate a wallet "bob" and sell something on eBay to "alice", but you screw her over and she registers a dispute with the address "bob". What are you going to do with the coins in the wallet "bob" to effectively spend them in some way? You're either going to transfer them to someone else or save them around and use them in a composite transaction later, right?

For it to work correctly a client would need to be extended to include a user interface to not accept transactions from some addreses without verification

[Kluge]

We need more support of this "taint" idea. More insistency on "anonymity" would be nice, too. Coin-mixing is very profitable... 

[aq]

There have been 1000s of threads about this stupid taint idea. Why does every newbie inhere start the same topic instead of educating himself why this is actually stupid.
Bitcoins are fungible, and luckily, will ever be.

[rjk]

Hey OP, I'm about to report your bitcoins as stolen, k?

[deepceleron]

https://developers.google.com/safe-browsing/

Wait, what were you talking about?

[hazek]

Hey OP, I'm about to report your bitcoins as stolen, k?

hahahahah LOL owned. I actually laughed out loud when I read this. hahahaha

[Gabi]

So OP bitcoins are tainted? Better we don't accept them!

[Transisto]

There have been 1000s of threads about this stupid taint idea. Why does every newbie inhere start the same topic instead of educating himself why this is actually stupid.
Bitcoins are fungible, and luckily, will ever be.

Bitcoin fungibility is debatable,

Is there even a DB to check if the BTC you just received are tainted and if so with what activity ?

How would you feel to be sent back BTC stolen from you to make a purchase.  I'd wish to do some investigation.

[hazek]

There have been 1000s of threads about this stupid taint idea. Why does every newbie inhere start the same topic instead of educating himself why this is actually stupid.
Bitcoins are fungible, and luckily, will ever be.

Bitcoin fungibility is debatable,

Is there even a DB to check if the BTC you just received are tainted and if so with what activity ?

How would you feel to be sent back BTC stolen from you to make a purchase.  I'd wish to do some investigation.

You are mistaken. Bitcoin fungibility is NOT debatable.

Yes, the history of how all coins change ownership is available but that's all there is because it's impossible to accurately and reliably link it with actual identities or activities. Yes you can do it roughly, but not 100% accurately and 100% reliably, and that pretty much sinks your point.-

[Elwar]

You can use the same website that they use to track dollars that have been used for bad things.

You DO check that site every transaction you make right? RIGHT??!?

[hazek]

A coin is a coin.
Pecunia non olet

Again, wishing it to be so doesn't make it so.

As much as I wish that was the case, it just isn't.

Unless you know of a method that would guarantee 100% accuracy and 100% reliability when connecting an identity and their actions with a specific Bitcoin transaction, a coin is a coin. No need to wish anything, it is so.