Despite concerns about consolidation among publishing houses, sales of the top 10 companies accounted for 55% of revenue of the 50 publishers that are on the list for both 2012 and 2011, down from 57% in 2011. 
One reason for the decline is the increasing number of publishers from emerging markets gaining sales worldwide. That has been especially true among publishers in the 20th to 50th spots on the ranking; total revenues from those 30 companies accounted for 25% of sales in 2012, up from 21% in 2011. In addition, several new companies have been added to the ranking this year, including two Chinese publishers and one from Russia, bringing the list to 60 publishers.

As has been true in recent years, publishers that specialize in scientific/technical/medical books and journals generated the highest revenue in 2012, followed by education and then trade. There seems little interest among the largest companies to broaden the areas in which they publish; each prefers to focus on one segment. That trend was seen most recently in the U.S., when John Wiley sold off its most consumer-oriented properties to concentrate on professional information. 
That, of course, is also the path Pearson took with its decision to merge its Penguin subsidiary with Random House, leaving Pearson with only its (very large) educational group. McGraw-Hill Companies also decided that it would be better off focusing on one area, this one outside of publishing altogether—financial services. MHC completed the sale of McGraw-Hill Education in early 2013 to a private equity group (the sale occurred before the final numbers for 2012 were released).

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