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Under the land charges act (1972), the 'general equitable charge', or class C(iii) charge, is an interest in unregistered land that is not secured by deposit of title deeds, and does not fall into any other category of equitable charge. In order to prevent class C(iii) becoming a dustbin for all kinds of equitable interest, some important interests are specifically exlcuded. In particular, you can't register an interest under a Trust in class C(iii). Probably the only interest that is likely to be encountered in this class now, and then only rarely, is an equitable mortgage.