16 institutions reported holding $202.7M of COMCAST CORP 3.15 28 DUE 02/15/28 (CMCSK) in SEC 13F filings for 2026-06-30. Largest institutional holders: IMC-Chicago, LLC ($88.8M), SIMPLEX TRADING, LLC ($47.2M), GROUP ONE TRADING LLC ($37.0M), HRT FINANCIAL LP ($18.0M), SUMMIT SECURITIES GROUP LLC ($2.6M). Source: SEC Form 13F.
| Rank | Institution | Value | Shares | Change |
|---|---|---|---|---|
| 1 | IMC-Chicago, LLC | $88.8M | 3.6M | Added |
| 2 | SIMPLEX TRADING, LLC | $47.2M | 1.9M | Added |
| 3 | GROUP ONE TRADING LLC | $37.0M | 1.5M | Added |
| 4 | HRT FINANCIAL LP | $18.0M | 733,700 | New |
| 5 | SUMMIT SECURITIES GROUP LLC | $2.6M | 104,200 | Added |
| 6 | Marathon Trading Investment Management LLC | $2.5M | 100,000 | New |
| 7 | TRIGLAV INVESTMENTS, D.O.O. | $2.2M | 2.5M | Hold |
| 8 | JPMORGAN CHASE & CO | $1.6M | 66,872 | Added |
| 9 | Maven Securities LTD | $1.2M | 49,000 | New |
| 10 | Burns Matteson Capital Management, LLC | $795,420 | 32,400 | New |
| 11 | CHESAPEAKE CAPITAL CORP /IL/ | $665,305 | 271 | New |
| 12 | New Age Alpha Advisors, LLC | $142,000 | 1,000 | New |
| 13 | Park Place Capital Corp | $45,173 | 40,000 | New |
| 14 | Financial Gravity Companies, Inc. | $2,940 | 3,000 | Hold |
| 15 | SG Americas Securities, LLC | $2,000 | 14,300 | Trimmed |
| 16 | Vinva Investment Management Ltd | $0 | 0 | Exited |
Source: SEC Form 13F filings · as of 2026-06-30