Actually, I don't believe this is correct. The weak form EMH claims that any information provided by the price history of a security should already be incorporated into the current price. You can claim that Technical Analysis (construed as patterns in charts and the like) isn't valid and that weak form EMH doesn't hold, if you believe that charting fails to correctly incorporate the relevant information from the price history.

Sorry, I read your statement too quickly. Missed the "weak". I thought you meant EMH holds (as I stated above).