Until 1950, Alcoa was concerned with its domestic market, while its Canadian
subsidiary Aluminum Limited (Alcan) took care of the international markets. From
1937 to 1957 it was under stricter than normal governmental supervision, pending
a final verdict in the U.S. vs Alcoa antitrust case. Alcoa's monopoly was
effectively ended by the disposal of Defense Corporation Plants after WWII by
the War Assets Administration.
This enabled Reynolds Metals Company and Kaiser Chemicals to become fully
integrated producers of primary aluminum. They were soon joined by Anaconda
Aluminum Company, a subsidiary of the copper-industry giant. In 1958 Harvey
Machine Tools Company began primary aluminum production, marking the end of
Alcoa's monopoly over the process which had led to its domination American
market.
