The dates may not match
A Schedule 13G can describe an ownership state tied to an event or reporting date and then become public on a later filing date. Another data source may be showing a quarter-end holdings dataset, a newer amendment, or an older snapshot.
If the dates differ, the percentages can differ even when both records were accurate for their own observation periods.
Beneficial ownership is not always a simple account balance
Schedule 13G reports beneficial ownership, including voting and dispositive power. A filing can contain several related reporting persons that describe overlapping authority over the same securities.
Adding every reporting-person share amount together can therefore overstate the economic position. Different sites may resolve that overlap differently.
The security class matters
Companies can have multiple classes of common stock, ADRs, units, or other securities. A percentage for one class should not be casually compared with a number calculated from another class or a company-wide share count.
Shares outstanding can change
Ownership percentage depends on both the reported beneficially owned shares and the denominator used for the class. Issuances, repurchases, conversions, and other changes in shares outstanding can move the percentage even if an institution’s reported share count stays the same.
A better way to compare sources
- Open the underlying SEC filing when possible.
- Match the issuer and exact security class.
- Compare the same reporting holder across the same date.
- Look for overlapping reporting persons before adding positions.
- Compare both shares and percent of class, not just one number.