Skill-biased technological change has long been linked to rising wage inequality. New technologies also allow firms to expand their scope of their operation. We formalize such quantity-biased technological change in a model where heterogeneous firms with decreasing returns to scale choose the size and quality of their white and blue-collar worker pools. We characterize the equilibrium assignment and calibrate the model to German matched employer-employee data. The calibration attributes substantial changes in the firm size distribution and in wages to quantity-bias.