It just depends on how you do it. Just because you have more money than the liquidity of the market doesn't mean your buy and sells are market manipulation. I

It just depends on how you do it. Just because you have more money than the liquidity of the market doesn't mean your buy and sells are market manipulation. I have bought things on the open market 100% above the prior market price, when I wanted them. Moving the asset's price 100% and sure enough many out of the loop people started FOMOing and buying more. Its the same principle for bearish positions too. In the securities market you can talk about your bullish or bearish rationale, and avoid sanctioning from regulators or private persons by disclosing your position. Ackman doubled down on that logic and did it very publicly. Although this is more a problem for bearish positions, the statements can't be lies or "intentionally misleading". In the past there were many naked shorts, where fake shares were sold into the public market causing impossible selling pressure. That is illegal now, for the most part, and as long as you aren't doing that it helps make sure you aren't manipulating the market, by the legal standard. Again, just because you can have an outsize affect on the price of the market and the mere presence of creating an advantageous circumstance, doesn't make it market manipulation or securities fraud.