actually ,you are in correct..you assume that they have no collateral backing...there are many structured forms of investment banking that use treasuries or cd's as collateral for principle against the loan.in these instances normal everyday banks can get involved or even syndicate together.they get a principle secured loan,which is very attractive in todays climate and the company basically gets a interest only loan....you just have to find an entity who believes in the project or company to provide the collateral..