After decades of being hidden from public view, the recent emergence of Su Shi's (1037–1101) Old Tree, Rock, and Bamboo has led to a long overdue reexamination of this famous scroll that many scholars regard as the single credible extant painting by the artist. Questions concerning authenticity have been at the forefront, and this has led to a focus on the scroll's impressive documentation, which begins with two poetic inscriptions contemporary to Su Shi, including one by the famed calligrapher Mi Fu (1052–1107). Yet, while scrutiny of the painting and its documentation has made a strong case for authenticity, it has largely avoided two seals on the painting that claim the actual authorial presence of Su and Mi. It is argued in this article that those two seals, which some have attributed to the later collector Yang Zun (ca. 1320–after 1368), should in fact belong to Su Shi and Mi Fu. Acknowledging their true provenance consequently provides an extraordinary entrée to reconstructing the dates and circumstances of both the painting and Mi's poetic inscription. Beyond this, we gain a glimpse of how the literati creatively employed inscriptional practices to enhance the communicative function of painting and calligraphy in the late eleventh century.