Value change is not trading
A position can grow 35% while the manager did nothing. Separating market movement from actual share changes.
Suppose a manager's stake in a company was reported at $1.0 billion last quarter and $1.35 billion this quarter. Did they buy? Not necessarily. If the share count is unchanged, the entire 35% rise is the stock's price move between the two quarter-ends. Value changes mix two ingredients — trading and market movement — and headlines routinely credit managers with "adding" value the market added for them.
How this site separates them
Share counts are the trading signal: they only change when the reported position changes. So every change table on this site leads with share changes, and treats value as context. Where a decomposition is shown, it is computed from the filings' own implied quarter-end prices (reported value ÷ reported shares): the share change priced at those implied prices estimates the trading contribution, and the remainder is the market-price contribution. Both are labeled estimates — implied prices inherit any rounding in the filing — and the method lives on the methodology page.
The portfolio-level version
The same confusion operates at portfolio scale: a manager's reported total can rise because markets rose, while they were net sellers all quarter. When you read a manager's quarter, look at the New/Increased/Reduced/Exited counts and the share-change column first, and the value totals second. The dollars follow the market; the share counts follow decisions.