A semi-strong Efficient market reflects all publicly available information, as found in annual reports, newspaper and magazine articles, prospectuses, announcements of new contracts, of a Merger, of an increase in the Dividend, etc. A semi-strong Efficient market is better than a Weak-form efficient market because current prices have to include historical information (as assumed by the Weak-form efficient market) and publicly available information. See also Efficient market.

(See Chapter 15 The financial markets of the Vernimmen)

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