Grading: It is da'if (weak) because of idtirab (inconsistency) in its isnad.
Technical note / Defect ('illah): This Ayman is the one whose biography was given by al-Bukhari in "al-Tarikh al-Kabir" 2/ 25, by Ibn Abi Hatim in "al-Jarh wa al-Ta'dil" 2/ 318 and in "al-Marasil" (43), quoting from his father, and by al-Daraqutni in "Su'alat al-Barqani" (40). These scholars identified him as "Ayman al-Habashi, the mawla of Ibn Abi Amr al-Makhzumi", the father of Abd al-Wahid bin Ayman, and they — and with them al-Nasa'i too, in "al-Sunan al-Kubra" after number (7399) — counted his narration from the Prophet (peace and blessings be upon him) as "mursal".

Details of the narration: In this hadith there is disagreement over Mansur bin al-Mu'tamir. Sufyan al-Thawri narrated it from him, and then there was disagreement over Sufyan too. Ubayd Allah bin Ubayd al-Rahman al-Ashja'i — as here in the author (al-Hakim)'s work — and Muhammad bin Yusuf al-Firyabi, in al-Nasa'i (7391) and Ibn Shahin's "Nasikh al-Hadith" (612), both narrated it from Sufyan al-Thawri with this same isnad.

Technical note / Defect ('illah): The two of them were contradicted by Abd al-Rahman bin Mahdi, in al-Nasa'i (7390), and by Mu'awiyah bin Hisham, in Abu al-Qasim al-Baghawi's "Mu'jam al-Sahabah" (66) and (67), al-Tahawi's "Sharh al-Ma'ani" 3/ 163, Ibn al-A'rabi's "al-Mu'jam" (813), al-Tabarani's "al-Kabir" (849) and Abu Nu'aym's "Ma'rifat al-Sahabah" (1009). The two of them narrated it from Sufyan al-Thawri, from Mansur, from Mujahid, from Ayman. Thus they did not mention "al-Hakam bin Utaybah" between Mansur and Mujahid. And Mu'awiyah, in his narration, joined Ata' (together) with Mujahid.

Details of the narration: This same route of Mu'awiyah bin Hisham was also recorded by al-Nasa'i in "al-Kubra" (7389) and "al-Mujtaba" (4943) through Mahmud bin Ghaylan, from him, from Sufyan, from Mansur, from Mujahid, from Ata'!

Details of the narration: It was also narrated by Abu Awanah al-Waddah bin Abd Allah al-Yashkuri from Mansur, and there was disagreement over him too (in stating the isnad):

Corroborating chains and supporting reports: It was narrated by Musa bin Isma'il al-Tabudhaki, in al-Bukhari's "al-Tarikh al-Kabir" 2/ 25, and by Abu Kamil Fudayl bin Husayn, in al-Bayhaqi 8/ 257, both from Abu Awanah, from Mansur, from al-Hakam, from Ata' and Mujahid, from Ayman al-Habashi, as his own statement (mawquf). In al-Bayhaqi's narration the words are: "It used to be said …", and then he mentioned the hadith.
Grading: Al-Bukhari preferred this narration and said: It is more authentic as mursal.

Technical note / Defect ('illah): The two of them were contradicted by Mu'awiyah bin Hafs al-Sha'bi, in Ibn Qani''s "Mu'jam al-Sahabah" 1/ 54 and al-Tabarani (850); he narrated it from Abu Awanah, from Mansur, from al-Hakam, from Ata' alone, from Ayman, who said: "In the time of the Messenger of Allah (peace and blessings be upon him), hands were cut off for the price of a shield", and so he narrated it as marfu'. (Yet) Musa and Abu Kamil are better at memorisation than Mu'awiyah al-Sha'bi.

Corroborating chains and supporting reports: It was narrated by al-Hasan bin Salih bin Hayy, in Ibn Abi Asim's "al-Ahad wa al-Mathani" (2650), al-Baghawi (69), al-Nasa'i (7393) and Abu Nu'aym's "Ma'rifat al-Sahabah" (1010), and by Shayban bin Abd al-Rahman al-Nahwi, in al-Bukhari's "al-Tarikh al-Kabir" 2/ 25; both of them from Mansur, from al-Hakam, from Ata' and Mujahid, from Ayman, who said: The thief (his hand) is cut off for the price of a shield, and in the time of the Messenger of Allah (peace and blessings be upon him) the price of a shield was one dinar or ten dirhams.

Corroborating chains and supporting reports: It was narrated by Ali bin Salih bin Hayy, in al-Nasa'i (7392), from Mansur, from al-Hakam, from Mujahid and Ata', from Ayman, who said: In the time of the Messenger of Allah (peace and blessings be upon him) the hand was not cut off except for the price of a shield, and its price at that time was one dinar. Thus he narrated both of its parts as marfu'.

Details of the narration: It was narrated by Sharik bin Abd Allah al-Qadi from Mansur, and there was disagreement over him too. It was narrated by Abu al-Walid al-Tayalisi, in al-Bukhari's "al-Kabir" 2/ 25 - 26; by Muhammad bin Sa'id bin al-Asbahani, in Ibn Abi Khaythamah's "Tarikh", second part (176); by al-Aswad bin Amir, in al-Baghawi (68); by Khalaf bin Hisham, also in al-Baghawi (65); and by Ali bin Hujr, in al-Nasa'i (7394). All five of them narrated from Sharik, from Mansur, from Ata' and Mujahid, from Ayman Ibn Umm Ayman, as marfu': "The hand is not to be cut off except for the price of a shield", and its price at that time was one dinar.

Technical note / Defect ('illah): Al-Asbahani and Khalaf did not mention Mujahid in their narrations.

Technical note / Defect ('illah): They were all contradicted by Yahya bin Abd al-Hamid al-Himmani, in al-Tahawi's "Sharh al-Ma'ani" 3/ 163, al-Tabarani 25/ (228) and Abu Nu'aym (7875); he narrated it from Sharik, from Mansur, from Ata', from Ayman Ibn Umm Ayman, from (his mother) Umm Ayman, who narrated it as marfu': "The thief's hand is not to be cut off except for a hajafah (shield)", and in the time of the Messenger of Allah (peace and blessings be upon him) it was valued at one dinar or ten dirhams.
Grading: Yahya al-Himmani is da'if (weak). And Abu Hatim said — as in "al-'Ilal" (1375) —: This is a mistake in two respects: first, the companions (students) of Sharik did not say "from Umm Ayman"; rather, they said "from Ayman Ibn Umm Ayman, from the Prophet (peace and blessings be upon him)". The second respect is that the trustworthy narrators narrate it from Mansur, from al-Hakam, from Mujahid and Ata', from Ayman, as his own statement (mawquf).

Corroborating chains and supporting reports: It was narrated by Jarir bin Abd al-Hamid, in al-Nasa'i (7395) and in al-Hakim's following narration, from Mansur, from Ata' and Mujahid, from Ayman, as mawquf.

Note / Clarification: This hadith passed in the previous narration from the narration of Ata' bin Abi Rabah from Ibn Abbas, and that is one of the forms of the disagreement over it from Ata'.

Technical note / Defect ('illah): This is how it occurs here in the manuscripts, and it is a mistake. What is well known is that the "Ayman" whom al-Shafi'i meant narrates from "Ibn Imra'at Ka'b" (the son of Ka'b's wife), whose name is "Tabi' bin Amir"; Ayman himself is not the son of Ka'b's wife.
Reference / Source: Al-Bayhaqi 8/ 257 transmitted this story from al-Hakim himself with this same isnad, in a more complete form than here. He said: Abu Abd Allah al-Hafiz informed us, Abu al-Abbas Muhammad bin Ya'qub narrated to us, al-Rabi' bin Sulayman informed us, he said: Al-Shafi'i said: I said to one of the people: This is the Sunnah of the Messenger of Allah (peace and blessings be upon him), that the hand be cut off for a quarter of a dinar or more; so how can you say that the hand is not cut off except for ten dirhams or more? And what is your proof for that? He said: It has been narrated to us from Sharik, from Mansur, from Mujahid, from Ayman, from the Prophet (peace and blessings be upon him), something similar to our view. I said: Do you know Ayman? The Ayman from whom Ata' narrated was only a young man, perhaps younger than Ata', and Ata' narrated from him a hadith from Tabi', the son of Ka'b's wife, from Ka'b; so this is munqati' (broken), and a munqati' hadith is not a proof. He said: Sharik bin Abd Allah has narrated from Mujahid, from Ayman Ibn Umm Ayman, the brother of Usamah through his mother. I said: You have no knowledge of our companions. Ayman, the brother of Usamah, was killed with the Messenger of Allah (peace and blessings be upon him) on the day of Hunayn before Mujahid was born, and he did not remain alive after the Prophet (peace and blessings be upon him) to narrate from him.

Technical note / Defect ('illah): This word is adopted from manuscript (B); the other manuscripts have "yadhkuru".