A study at the University of Montreal shows that the market share of the five largest research publishing houses reached 50% in 2006, rising, thanks to mergers and acquisitions, from 30% in 1996 and only 20% in 1973. “Overall, the major publishers control more than half of the market of scientific papers both in the natural and medical sciences and in the social sciences and humanities,” said Professor Vincent Larivière of the School of Library and Information Science, who led the study.

A press release from the University of Montreal can be found here.