The Competitive Effects of Mergers: Stock Market Evidence from the U.S. Steel Dissolution Suit

Abstract

We apply and extend the Eckbo-Stillman event-study methodology to investigate the competitive effects of the U.S. Steel consolidation. In contrast to previous event studies, we examine the stock market reactions of downstream firms, thereby enabling us to estimate the net effect of a merger or antitrust action on product market prices. Specifically, we examine the stock market reactions of U.S. Steel, major steel industry rivals, and downstream customers to events from the unsuccessful dissolution suits begun in 1911 and decided in 1920. The pattern of reactions implies that the dissolution of U.S. Steel would have lowered steel prices and raised output.