Abstract: A system and method for auto-inoculating a bioreactor in a seed train process includes an expansion chamber for expanding an initial cell stock to a viable cell density, a bioreactor for inoculation with the expanded cell stock; a fluid communication path between the expansion chamber and the bioreactor; a pump for controlling fluid flow through the fluid communication path; a Raman spectrometer for generating Raman spectral data; a multivariate model providing predictions of processing variables in the expansion chamber; and a computer system for controlling the pump to effect auto-inoculation of the bioreactor from the expansion chamber, through the fluid communication path, when the computer system determines from the Raman spectral data that one or more predefined trigger events have occurred.