1. A method for protecting an integrated circuit chip design, comprising: storing in memory an original circuit description of an integrated circuit core comprising a set of nodes; selecting a plurality of modification nodes from the set of nodes; inserting a sequential structure into the original circuit description to provide a modified circuit description, the plurality of modification nodes operating as inputs to the sequential structure, the modified circuit description corresponding to an obfuscated version of the original circuit description that enables at least an evaluation of the original circuit description; and storing the modified circuit description in memory, wherein the modified circuit description is functionally equivalent to an original circuit description upon application of the key.