The defaulted Argentine Bonds are subject to foreign law because that is what was stated in the bonds when they were issued in order to make them more marketable.
Most of the bonds that Greece recently defaulted on were subject to greek law, which allowed them to force the holders to accept a debt exchnage by ammending Greek law and inserting a collective action clause, however there was a few billion in Greek bonds that had been issued subject to I believe English law, and there we holdouts on those who recently got paid back full value, also the new bonds issued in Greece as part of the debt swap are now subject to English law, though I think they do have a collective action clause in them.
Most of the bonds that Greece recently defaulted on were subject to greek law, which allowed them to force the holders to accept a debt exchnage by ammending Greek law and inserting a collective action clause, however there was a few billion in Greek bonds that had been issued subject to I believe English law, and there we holdouts on those who recently got paid back full value, also the new bonds issued in Greece as part of the debt swap are now subject to English law, though I think they do have a collective action clause in them.