Stablecoins lack a clear, universal legal definition, hindering their integration into global financial regulatory sandboxes. The Financial Stability Board defines them as cryptoassets designed to maintain stable value relative to a reference asset or basket, yet the term "stablecoin" is a market label, not a guarantee of stability. Jurisdictions vary widely in their regulatory approaches—some classify stablecoins as payment instruments, others as securities or e-money. This inconsistency complicates sandbox inclusion, which requires clear legal frameworks for testing. Sandboxes, like those in the UK or Singapore, demand defined asset classifications to assess risks and compliance. Without standardized definitions, regulators struggle to balance innovation with oversight, risking regulatory arbitrage. Efforts like the EU’s MiCA regulation aim to address this, but global consensus remains elusive. Stablecoins’ diverse designs—algorithmic, fiat-backed,