How much capital in the US stock market is considered 'large capital'?

The SEC has a clear definition for 'large capital'. According to Rule 13h-1 of the Securities Exchange Act, a 'Large Trader' refers to any individual or entity that trades US exchange-listed stocks and options equal to or exceeding 2 million shares or $20 million in a single day, or equal to or exceeding 20 million shares or $200 million in a single month. Reaching this threshold requires filing Form 13H with the SEC.

For investors like Warren Buffett and Duan Yongping, daily transactions require reporting via 13H (real-time), and quarterly holdings must be reported via 13F (public). The SEC knows every move they make. Retail investors cannot see real-time data, but once the 13F reports are released, they can still copy their 'lagging moves'.

However, the regulatory definition of 'large' and the market's perception of 'large' are two different things. Micron's market cap is approximately $1 trillion, with an average daily turnover exceeding $16 billion. A $20 million order thrown into this pool accounts for less than 0.1% of the total daily turnover. True 'large capital' that can influence stock prices depends on relative liquidity—for a stock at Micron's level, only orders worth hundreds of millions of dollars carry weight. The position held by Michael Burry, the 'Big Short', is nothing more than a fraction compared to Micron's daily turnover of tens of billions—he influences stock prices through his reputation, not just his money.

As for Micron, it hit an intraday low of $854.79 on July 27, having fallen more than 30% from its high of $1,255 at the end of June.

$Micron Tech(MU.US)

$SK Hynix(SKHY.US)

$XL2CSOPHYNIX(07709.HK)