Since Thamphthis' name was found in the historical works of Manetho, the Aegyptiacae,[3] Egyptologists are trying to connect this ruler with contemporary kings to build up a continuous chronology, which resulted in controversies and debates.

As early as 1887, Eduard Meyer viewed Thamphthis as a mere usurper, who was not allowed to be mentioned in royal annals or have his own mortuary cult because he gained the throne illegitimately.

[5] Winfried Seipel and Hermann Alexander Schlögl instead postulate that the historical figure behind Thamphthis could have been queen Khentkaus I.

[6] This theory is supported by Khentkaus being depicted in her mortuary temple as a ruling pharaoh with nemes-headdress, king's beard and uraeus-diadem on her forehead.

[8][9] In the Manethonian tradition of the historian Sextus Julius Africanus, who translated Manetho, Thamphthis is described as the last ruler of the 4th dynasty with a reign of nine years.

For this reason it cannot be excluded that Thamphthis' name was originally present in this document too, since the Aegyptiacae of Manetho are mostly consistent with the Turin Canon.

[12] A rock inscription in the Wadi Hammamat made in the Middle Kingdom presents a list of the cartouche-names of Khufu, Djedefre, Baufra and prince Djedefhor (also recorded as Hordjedef).

[13] The tomb inscriptions of several high officials, princes and priests do not preserve any evidence that some kind of internal political conflict had arisen or that a usurper had seized the throne of Egypt.

Prince Sekhemkare reports about his career under the kings Khafre, Menkaura, Shepseskaf, Userkaf and even Sahure, but makes no mention of Thamphthis.

[14] The late Patrick F. O'Mara in a GM 158 paper notes that "no royal monument private tomb in the cemeteries of Gizeh and Saqqara record names of any other [except the aforementioned] kings for the [fourth] dynasty.