What does "% of portfolio" mean?
A holding's value as a share of the fund's total 13F holdings, also called its manager weight. A stock at 10% is a big bet for the fund; one at 0.1% barely matters to it.
The change in it is shown in percentage points: a stock going from 2% to 5% of a portfolio has changed by +3 points. It moves when the fund trades, and also when the stock's price moves against the rest of the portfolio.
Because 13Fs leave out shorts, cash and most non-US holdings, these weights are shares of what's in the 13F, not of everything the fund owns.
Related pages: Top hedge funds