[en] The internal ionization accompanying the first-forbidden unique electron-capture decay of ⁴¹Ca was investigated. The integrated probability of electron ejection with energy greater than 38 keV was found to be (0.17±0.02) x 10^-5 per K-capture. In this energy range, the measured spectrum of ejected electrons is fairly close to predictions of the simple theory of Primakoff and Porter, and of the relativistic theory of Mukoyama et al. By a model-dependent extrapolation of this spectrum toward low energies, the total probability of internal ionization in ⁴¹Ca was estimated and compared with relevant experimental results for other isotopes. (orig.)