In the context of Efficient Market Hypothesis (EMH), what does weak form imply?

The weak form of the Efficient Market Hypothesis (EMH) posits that all past price information is already incorporated into current stock prices, and therefore, it is essentially worthless for predicting future price movements. This means that technical analysis, which relies on historical price and volume data to forecast future market behavior, should not result in consistent excess returns, as the market has already assimilated all available past information.

Under this hypothesis, it is assumed that market participants act rationally, and any patterns or trends that could have been identified through historical price data have already been exploited and thus neutralized by other market participants. Consequently, in weak form efficiency, the randomness of stock price movements indicates that past performance is not a reliable indicator of future performance, which is a foundational concept in the field of technical analysis and investment strategies.