GJ 4276 is a cool M-dwarf (about 0.41 solar masses, 3,387 K, 0.41 solar radii), 21.3 light-years from Earth. GJ 4276 b is a 0.05-Jupiter-mass companion, with an orbital period of 13.4 days, at 0.082 AU from its star, on an eccentric orbit (e ≈ 0.37), discovered in 2019 via radial velocity. The planet betrayed itself through the star's reflex motion — a technique that first revealed worlds around Sun-like stars in the 1990s and remains a workhorse of exoplanet discovery. The planet's marked eccentricity suggests past scattering events or perturbations from unseen companions.