<p>The advent of novel technologies has bolstered the idea of extended memory, where memory processes extend beyond the human body or brain. However, investigations of extended memory, and extended cognition more generally, do not address how biological componentry might be externalized from the body and into artifacts. In the paper, I introduce and explore a case where human engrams are externalized into exograms, stored via organic data memory technologies, and reimplanted later. This case involves the same medium of memory storage in internal and external systems, which I call a <i>biological memory extension</i>. Further, it creates a concern about a blur between where agent ends and artifact begins, highlighting a potentially inconsistent consideration of the boundary between the two. These concerns reflect the need for us to answer a fundamental question: for extended memory, must the artifact merely extend beyond our bodies, or must it extend beyond our biology?</p>