3 institutions reported holding $1.0M of VANGUARD MUN BD FDS (VWSTX) in SEC 13F filings for 2026-06-30. Largest institutional holders: SIMPLEX TRADING, LLC ($950,904), GROUP ONE TRADING LLC ($60,696), IMC-Chicago, LLC ($0). Source: SEC Form 13F.
| Rank | Institution | Value | Shares | Change |
|---|---|---|---|---|
| 1 | SIMPLEX TRADING, LLC | $950,904 | 18,800 | Trimmed |
| 2 | GROUP ONE TRADING LLC | $60,696 | 1,200 | New |
| 3 | IMC-Chicago, LLC | $0 | 0 | Exited |
Source: SEC Form 13F filings · as of 2026-06-30