This paper studies the hypothesis that large firms have more bargaining power with suppliers than do small firms, using data from the cable television industry. Employing techniques from the “new empirical lo,” the effect of owner size on marginal costs is inferred from the effect of owner size on observable product market choices. In the cable industry, the downstream firms decide how many subscriptions of cable to sell and how many channels to offer in the cable package. lf large firms have lower costs than small firms, then large firms should be willing to supply more than small firms, at all prices. The effects of bargaining power are identified separately from the effects of scale economies by exploiting the structure of the cable industry. Scale economies, in the cable industry, are likely to stem from regional size, while bargaining power is likely to stem from national size. By controlling for regional size, estimates of the effect of owner national size on the willingness to supply cable subscriptions and to offer channels indicate that large downstream firms offer significantly more subscriptions and channels at all prices than do small downstream firms. These results provide some of the first systematic, industry-specific, evidence consistent with the bargaining-power hypothesis.