Lost Legacy (1941) is a novella by science fiction writer Robert A. Heinlein.
The story was rejected by John W. Campbell for Astounding. It was then accepted by Frederick Pohl, and was published in the November 1941 issue of Super Science Stories under the title "Lost Legion" and the pseudonym Lyle Monroe. The story was collected as "Lost Legacy" under Heinlein's own name in the book Assignment in Eternity (1953).
Campbell, when rejecting the story, said that it was good, not great. However, Pohl said that "Some of Heinlein's early work came to me because John didn't have the wit to buy it". He also said that this piece was published under a pseudonym because he was only paying Heinlein "something like a quarter of a cent a word".