There is considerable interest from the wider scientific community in the heritability of epigenetic states across generations, and this has arisen as a result of a series of studies in mice [1],[2], flies [3], plants [4],[5], and yeast [6] over the past decade. These studies have identified genetic elements at which epigenetic states appear to be inherited through meiosis. The Lamarckian implications of these findings are hard to avoid. Transgenes, transposons, and other “foreign DNA” appear to be particularly prone to transgenerational epigenetic inheritance (reviewed in [7]). In this issue of PLoS Genetics, Singh et al. [8] describe the identification of a locus in the genome of maize at which a transposon, silenced by an RNAi-based mechanism, becomes reactivated over subsequent generations. This article reports an activating “position effect,” i.e., an integration site that is associated with the reversal of a previously established silent state in plants.