Risk management

It's hard to build an online marketplace when the same products can be found just as easily on Amazon and eBay. But Reverb has found success in fine-tuning the way it handles data and payments.

Banks and payment companies have long been wary of the political and reputational risks of supporting gun sellers. But gun sellers know their customers better than most other merchant categories.

As financial services companies cool on gun sales, alternative currencies may step in to pick up the slack.

For much of the last decade, credit card companies and issuers have fine-tuned security to the point where if any suspicious activity occurs on a cardholder account, that cardholder will receive an alert. That same sort of transaction and behavioral analytics is starting to come into other business sectors and walks of life.

Payment processors and banks are being called on to cut off funds to white supremacist groups, but there are practical and legal limits to what firms can do.

Even the most honest customers can look risky if they frequently travel. Their movements can throw off traditional vetting techniques that authenticate transactions by looking at location as a risk factor.

The three bitcoin wallets that are linked to the WannaCry malware, which hit hundreds of thousands of networks using Microsoft Corp.’s operating system in 150 countries, were emptied out Thursday morning, analysts have confirmed.