In the era of embedded MRAM (eMRAM) technology evolution for the replacement of eFlash and SRAM, the correlation between magnetic immunity (MI) and eMRAM reliability must be well understood to realize the mass production. In this paper, we have classified the types of MIs and also established the MI guidelines for eMRAM product reliability for the first time. From 40Mb eMRAM package-level data, our proposed MI specifications guarantee the 10 years of reliability at operating temperatures ranging from -40°C to 150°C, which covers all industrial-grade and automotive-grade-1 applications.