Fl. early 8th/14th c. In addition to his compositions, Bayhaqī copied Ṭūsī's Taḥrīr al-Majisṭī in 722 H. [1322-3) at Ṣulṭanīya (London, British Library Or 1148). According to the Loth catalogue, Bayhaqī transcribed it from a copy which had been taken from the author's own copy and Bayhaqī collated it with another copy at Ṣulṭanīya in the Madrasa Rashīdiyya.