Last month I bought some IDB long term bonds yielding 17%. IDB is Israel's largest holding corporation and it is unimaginable that it will fall. Yet it lost 50% of its market value and now yields more than 35%. The problem is its extreme pyramidal structure, Gandan, Nochi Dankner (pic) holding corp at the top of the pyramid, owes about 200 million dollars while the value of its stock on TASE is half of it - so the banks are holding its lifeline. It is difficult to calculate, but some say that IDB has negative net worth. But in a living ongoing business that is not fatal, and it may revive. As for now, I am losing but very optimist. Should I buy more these cheap bonds? Is this an investment opportunity?