From 1897 – 1904
During this period merger took place between the firms which were anti-competition and enjoyed their dominance in the market according to their productivity in sectors like electricity, railways, etc. Most of the mergers during this period were horizontal in nature and occurred between the steel, metal and construction industries.
From 1903 – 1905
From 1916 – 1940
Unlike the preceding phase, this period concentrated on mergers between oligopolies, rather between anti-competitive firms. The mergers and acquisitions process was triggered by the financial boom which was seen after the World War I. The expansion further lead to developments in the fields of science and technology and the emergence of infrastructure firms which provided services for required growth in railroads and transportation by automobiles. The government strategies laid in 1920s made the corporate ambiance supportive enough for firms to work in harmony. Financial institutions like government and private banks also played a significant part in aiding the mergers and acquisitions process.
The mergers which occurred during 1916-1929 were horizontal or multinational in nature. Most of these industries were the manufacturers of metals, automobile tools, food commodities, chemicals, etc.
Most of the mergers which took place during the first phase were considered as unsuccessful for not being efficient enough to attain the required competence. The crash was stimulated by the decelerating of the world's financial system in 1903, which was followed by a stock market collapse in 1904. During this phase the authorized structure was not encouraging either. Later the apex judiciary body issued its directive on the anti-competitive mergers stating that they could be de-merged by implementing the Sherman Act.