What makes you think that? Have you seen a discrepancy between your projections of future cash flows and therefore your valuation, as compared to the value the market is at right now?
I think it's safe to say the market isn't rational when Zoom Technologies is up nearly 900% when it's completely unrelated to Zoom Video and not actually operating.
I don't think you can really compare people accidentally buying the wrong ticker to investors unable to place valuations based on virus uncertainties. They were buying the wrong stock before the virus hit more than a year ago.
The wrong stock increased faster than the real stock. Volume matters too but when the underlying causes are irrational, how can any pricing be logical over any period longer than a few days?
5-10% swings are definitely not sane. I think there was technically a 3-day bull market last week, even though there wasn't much news that wasn't foreseeable on Monday.
I read that a lot of hedge funds running heavily leveraged, marginally profitable strategies have been deleveraging. That's a pretty rational response. Some of the movement is emotional, but some is driven by more rational concerns.
Microsoft stock is up more than 4% today after this news. It's almost foolish to claim anything is priced in because the stock market is a Keynesian contest. Claiming it's priced in means you know how every other portfolio and hedge fund manager is going to react to news. Some might be slow to react, some might overreact, etc. Nobody can read minds. Thus it's almost impossible to claim anything is priced in.
