jats:titleAjats:scbstract</jats:sc> </jats:title>jats:pIn the Hamiltonian formulation of chiral 2jats:italick</jats:italic>-form electrodynamics, the 2jats:italick</jats:italic>-form potential on the (4jats:italick</jats:italic> + 1)-space is defined up to the addition of either (i) a closed 2jats:italick</jats:italic>-form or (ii) an exact 2jats:italick</jats:italic>-form, depending on the choice of chirality constraint. Case (i) is realized by the Floreanini-Jackiw 2D chiral boson (for jats:italick</jats:italic> = 0) and its Henneaux-Teitelboim generalisation to jats:italick ></jats:italic> 0. For all jats:italick</jats:italic>, but focusing on the 6D case, we present a simple Lorentz-invariant Hamiltonian model that realizes case (ii), and we derive it from Siegel’s manifestly Lorentz invariant Lagrangian formulation.</jats:p>