CSS LLC IL
Q2 2026 Form 13-F
CHICAGO, ILLINOIS
CIK 0001103646
· Institutional investment manager
$2.6B Reported Value Total
Reported value
$2.6B
Quarter over quarter
+8.4%
Holdings
694
Top-10 concentration
35.0%
Key People
Named on the latest Form 13-F filing — not necessarily an owner
Mitchel Bialek
CCO
Filing Navigation
13F Metrics
Loading 13F Metrics
Q2 2026 13F record
Q2 2026 13F filing summary
| Period of report | June 30, 2026 |
|---|---|
| Filed | August 14, 2026 |
| Form | 13F-HR |
| Reported value | $2.6B |
| Positions | 694 |
| Change in reported value | +23.0% |
| New positions | 211 |
| Exited positions | 184 |
| Position turnover | 45.0% |
| Top-10 concentration | 35.0% |
13F filings by quarter
| Quarter | Positions | Value |
|---|---|---|
|
Q2 2026 13F
Filed Aug 14, 2026
|
694 | $2.6B |
|
Q1 2026 13F
Filed May 15, 2026
|
652 | $2.1B |
|
Q4 2025 13F
Filed Feb 17, 2026
|
649 | $2.2B |
|
Q3 2025 13F
Filed Nov 13, 2025
|
604 | $2.2B |
|
Q2 2025 13F
Filed Aug 14, 2025
|
590 | $2.1B |
|
Q1 2025 13F
Filed May 15, 2025
|
550 | $1.8B |
|
Q4 2024 13F
Filed Feb 18, 2025
|
541 | $2.3B |
|
Q3 2024 13F
Filed Nov 14, 2024
|
496 | $2.2B |
|
Q2 2024 13F
Filed Aug 14, 2024
|
490 | $2.0B |
|
Q1 2024 13F
Filed May 15, 2024
|
483 | $1.7B |
|
Q4 2023 13F
Filed Feb 14, 2024
|
447 | $1.7B |
|
Q3 2023 13F
Filed Nov 14, 2023
|
488 | $1.5B |
|
Q2 2023 13F
Filed Aug 14, 2023
|
526 | $1.6B |
|
Q1 2023 13F
Filed May 15, 2023
|
489 | $1.5B |
|
Q4 2022 13F
Filed Feb 14, 2023
|
617 | $1.8B |
|
Q3 2022 13F
Filed Nov 14, 2022
|
666 | $2.1B |
|
Q2 2022 13F
Filed Aug 15, 2022
|
732 | $2.5B |
|
Q1 2022 13F
Filed May 16, 2022
|
805 | $2.8B |
|
Q4 2021 13F
Filed Feb 14, 2022
|
900 | $2.8B |
|
Q3 2021 13F
Filed Nov 15, 2021
|
853 | $2.4B |
31 earlier quarters on file — choose one from the quarter menu above.
Top 20 holdings · Q2 2026
| # | Holding | Reported value | % of portfolio |
|---|---|---|---|
| 1 | LITE 0.5 06/15/28 LUMENTUM HLDGS INC | $245.6M | 9.56% |
| 2 | HPEPRC HEWLETT PACKARD ENTERPRISE C | $149.3M | 5.81% |
| 3 | ECHO 3.875 11/30/30 ECHOSTAR CORP | $137.4M | 5.35% |
| 4 | APOPRA APOLLO GLOBAL MGMT INC | $82.8M | 3.22% |
| 5 | BACPRL BANK OF AMER CORP | $63.3M | 2.46% |
| 6 | WOLF 2.5 06/15/31 WOLFSPEED INC | $54.2M | 2.11% |
| 7 | SMCIP SUPER MICRO COMPUTER INC | $45.3M | 1.76% |
| 8 | CORZW CORE SCIENTIFIC INC NEW | $44.2M | 1.72% |
| 9 | MCHPP MICROCHIP TECHNOLOGY INC. | $43.0M | 1.67% |
| 10 | NET 0 08/15/26 CLOUDFLARE INC | $33.5M | 1.31% |
| 11 | AKAM 1.125 02/15/29 AKAMAI TECHNOLOGIES INC | $29.6M | 1.15% |
| 12 | GME P GAMESTOP CORP | $27.2M | 1.06% |
| 13 | ALBPRA ALBEMARLE CORP | $26.1M | 1.02% |
| 14 | CNP 4.25 08/15/26 CENTERPOINT ENERGY INC | $25.3M | 0.98% |
| 15 | EQXCN 4.75 10/15/28 EQUINOX GOLD CORP | $25.1M | 0.98% |
| 16 | BAPRA BOEING CO | $23.6M | 0.92% |
| 17 | RIG 4.625 09/30/29 * TRANSOCEAN INC | $23.5M | 0.91% |
| 18 | EPPRC EL PASO ENERGY CAP TR I | $22.6M | 0.88% |
| 19 | RSP INVESCO EXCHANGE TRADED FD T | $22.1M | 0.86% |
| 20 | VOO VANGUARD INDEX FDS | $22.1M | 0.86% |
Values as reported on the Q2 2026 Form 13F. Every position is in the holdings table below.