A 2003 attempt by Christopher Brochu included "Albertosaurus", "Alectrosaurus", "Alioramus", "Daspletosaurus", "Gorgosaurus", "Tarbosaurus" and "Tyrannosaurus" in the definition. Holtz redefined the clade in 2004 to use all of the above as specifiers except for "Alioramus" and "Alectrosaurus", which his analysis could not place with certainty. However, in the same paper, Holtz also provided a completely different definition, including all theropods more closely related to "Tyrannosaurus" than to "Eotyrannus". The most recent definition is that of Sereno in 2005, which defined Tyrannosauridae as the least inclusive clade containing "Albertosaurus", "Gorgosaurus" and "Tyrannosaurus".