Transmission spectra of LHS 1140 b for each of the four visits focused on wavelengths around the 1.083 μm He triplet (which is unresolved at the spectral resolution of NIRISS/SOSS; R ∼ 600). Pixel-level transit depths (i.e., one transit depth per pixel column on the detector) are shown in black. Posterior draws for several model fits are shown with colored lines: a flat continuum with no absorption lines (blue); a flat continuum with a Gaussian He absorption feature at 1.083 μm (orange); a flat continuum with a Gaussian He absorption feature with its amplitude fixed to that observed by C. Cherubim et al. (2026) using WINERED in 2024 (green).