The resemblance between an inscribed terracotta dish from approximately 100 BCE found in Sulur, near Coimbatore in Tamilnadu, South India and a three-sided tablet found in Harappa from the ancient Indus Civilization. The Harappan tablet is roughly 2,000 years older. Since the ancient Indus script is thought to have died out by 1900-1700 BCE, the discovery of an apparently similar inscription deep in south India where Indus culture is not known to have penetrated is a curious anomaly to received opinion.

At the same time, intriguing new finds like the recent Stone Celt Axe Indus Sign discovery, also in Tamil Nadu, suggest that Indus signs may have traveled further south than generally believed.