The Maitrayaniya Upanishad was probably composed in late 1st millennium BCE, likely after Atharva Veda texts such as the Mundaka Upanishad and Prashna Upanishad, but its precise chronology is unclear and contested [REF].
Deussen states that the Upanishad is chronologically significant because its author(s) takes for granted the concepts and ideas found in Samkhya and Yoga schools of Hinduism, which must have been established by the time Maitri Upanishad was composed [REF].