Bitfinex: you lend money and get paid back whether or not the person makes profits. If they are losing money, the system does a margin call before they go bankrupt - so the system is able to pay you back.
but do you get lending interest if they get a margin call?
Yes. The creator of Bitfinex has pointed this out several times. Once a position gets a margin call, the Bitfinex platform is taking the risk for getting that position actually liquidated. Of course, this means, that in case of an extreme situation, when the market price slips away catastrophically, the platform can go bankrupt. This is an essential risk of any Contract-for-Difference platform. Thus, for a lender, this is the essential counterparty risk.
What the platform can do is to have some kind of insurance contract. And if I understand the latest announcement(*) from the Platform operator correct, he is currently negotiating with some investors exactly for this purpose. He is also about to get this thing properly incorporated. Right now it is labelled as "beta", but has taken on some momentum during this rally.
(*) see this message in the ProjectDevelopment section
Thanks man, good information. Seems like an interesting platform, but proper insurance is a very desirable thing in a market as volatile as bitcoin (especially with gox lagging out at criticial times and all).
"soon"... virtex will offer shorting, and you will be able to lend your bitcoins (with interest) on havelockinvestments.com
not sure how it will all work, but defiantly something to look forward too.
