I get how both can cause an increase in stock price in practice. Coming as I was immediately from the logic puzzle thread, I was primed to think differently ab

I get how both can cause an increase in stock price in practice. Coming as I was immediately from the logic puzzle thread, I was primed to think differently about the statements. A very literal (and a bit naive) reading of the article leads one to conclude that: merger -> increased price not merger -> increased price This allows us to conclude that knowledge of (merger|not merger) gives us no extra information about whether price should increase. Again, I am interpreting strictly as a pair of logical statements.