What are small, medium and large trades and stakes?
They size a fund's trade or holding against its whole portfolio. A trade worth under 0.1% of the fund's portfolio is small, 0.1% to 1% medium, and 1% or more large. A stake under 0.5% of the portfolio is small, 0.5% to 5% medium, and over 5% large.
Sizing against the portfolio means a $5 million purchase is a large trade for a $200 million fund and a small one for a $200 billion fund: what matters is how much of its money the fund moved.
A trade's size is the shares bought or sold, at the stock's average price that quarter, as a share of the fund's total 13F holdings. Buys in a fund's first 13F aren't counted as buys, since every holding in it looks new.
Counts like "large buys" on stock pages and in the screener let you look past the many small trades big institutions make every quarter.
Related pages: Stock screener