Each of the following would tend to weaken the semi-strong form Efficient Market Hypothesis EXCEPT:
A) There is publicly available information that Boeing Aircraft has procured a contract to build 25 planes for the U.S. Government and the price of Boeing quickly goes up.
B) ACG, Inc. performed well for the past six months, but they just lost a major distribution contract, but the price of ACG stock continues to go up.
C) Louisville Slugger, Inc., gets a contract to supply bats for Little League play, a contract it never had before, and stock price remains stable.
D) Muguet Company consistently underperforms the market in October, but outperforms the market in May.

Question

Quizplus · Accepted Answer

The semi-strong form of the Efficient Market Hypothesis (EMH) posits that all publicly available information is already reflected in stock prices. Therefore, if the price of Boeing quickly goes up after the public announcement of a new contract, it supports the semi-strong EMH, as the market is efficiently incorporating new public information into the stock price.

Each of the Following Would Tend to Weaken the Semi-Strong