Q2 2026 13F · SEC CIK 1600133
13D Management LLC
Mutual fund managerFiled 2026-08-14 for Q2 2026. Open the filing ↗ · All SEC filings ↗
- Reported 13F value
- $71.3M
- Reported positions
- 11
- Top holdings a year, 3 yrs
- +16.1%
- Assets under management
- $99.4M
13D Management LLC is a mutual fund manager that reported 11 positions worth $71.3M in its Q2 2026 13F, filed 2026-08-14. Its largest holdings were Viasat Inc Com (VSAT, 15.9%), Twilio Inc (TWLO, 11.3%), Mercury Sys Inc (MRCY, 10.4%). A portfolio copying its top holdings returned 16.1% a year over the last 3 years, against 20.4% for the S&P 500.
13D Management LLC holdings all 11 positions.
Weights are shares of the filer's total reported 13F value, compared with Q1 2026. Share changes may reflect splits; weight changes also reflect price moves. A 13F shows long US-listed positions only, up to 135 days after the fact.
| Stock | % of 13F value | Share change | Reported value |
|---|---|---|---|
| VSATViasat Inc Com | 15.9% | -23.4% | $11.3M |
| TWLOTwilio Inc | 11.3% | -35.8% | $8.0M |
| MRCYMercury Sys Inc | 10.4% | +0.0% | $7.4M |
| PSOPearson PLC | 10.2% | +0.0% | $7.3M |
| ALVAutoliv Inc | 9.1% | +0.0% | $6.5M |
| CRLCharles Riv Labs Intl Inc | 8.2% | +0.0% | $5.9M |
| SNPSSynopsys Inc | 7.9% | — | $5.6M |
| EXELExelixis Inc | 7.7% | +0.0% | $5.5M |
| ETSYEtsy Inc | 7.6% | +0.0% | $5.4M |
| ITGRInteger Hldgs Corp | 6.2% | +0.0% | $4.4M |
| FUNSix Flags Entertainment Corp | 5.6% | +0.0% | $4.0M |
What 13D Management LLC bought and sold in Q2 2026, against Q1 2026.
New positions
- SNPS Synopsys Inc7.9% of 13F
Added to
No position grew by more than 5%.
Reduced
- TWLO Twilio Inc-35.8% shares
- VSAT Viasat Inc Com-23.4% shares
Sold out
- ACHC Acadia Healthcare Company inwas 10.7%
- TRIP Tripadvisor Incwas 5.0%
- WK Workiva Incwas 4.8%
Share counts compared with the Q1 2026 13F; a split also changes share counts.
How the holdings did against the S&P 500.
- 1 year
- +37.4% /yr
- S&P 500 +20.1%
- 3 years
- +16.1% /yr
- S&P 500 +20.4%
- 5 years
- +8.7% /yr
- S&P 500 +11.6%
A portfolio of the filer's 20 largest 13F positions, weighted by value, bought the trading day after each 13F was filed and held until the next one was: what copying this filer could have earned. 13Fs show long US-listed positions only, so this is an estimate of the stock picks, not the fund's reported returns.
Reported 13F value by quarter.
| Quarter | 13F value | Positions |
|---|---|---|
| Q2 2026 | $71.3M | 11 |
| Q1 2026 | $64.5M | 13 |
| Q4 2025 | $84.0M | 16 |
| Q3 2025 | $104.3M | 18 |
| Q2 2025 | $109.6M | 20 |
| Q1 2025 | $113.4M | 21 |
| Q4 2024 | $135.0M | 21 |
| Q3 2024 | $136.4M | 22 |
| Q2 2024 | $137.1M | 21 |
| Q1 2024 | $163.8M | 28 |
| Q4 2023 | $169.9M | 29 |
| Q3 2023 | $160.7M | 28 |
Questions about 13D Management LLC's portfolio
What stocks does 13D Management LLC own?
13D Management LLC's latest 13F, for Q2 2026 and filed Aug 14, 2026, lists 11 positions worth $71.3M. The largest are Viasat Inc Com (VSAT) at 15.9%, Twilio Inc (TWLO) at 11.3%, Mercury Sys Inc (MRCY) at 10.4%, Pearson PLC (PSO) at 10.2% and Autoliv Inc (ALV) at 9.1%.
What did 13D Management LLC buy last quarter?
In Q2 2026, 13D Management LLC added a new position in Synopsys Inc (SNPS), compared with its Q1 2026 filing.
What did 13D Management LLC sell last quarter?
In Q2 2026, 13D Management LLC sold all of Acadia Healthcare Company in (ACHC), sold all of Tripadvisor Inc (TRIP), sold all of Workiva Inc (WK), Twilio Inc (TWLO) (-35.8% shares) and Viasat Inc Com (VSAT) (-23.4% shares), compared with its Q1 2026 filing.
How has 13D Management LLC's portfolio performed?
A portfolio copying 13D Management LLC's 20 largest 13F holdings each quarter, from the day each filing was public, returned +16.1% a year over the last 3 years, against +20.4% for the S&P 500. Over 1 year: +37.4% against +20.1%. Over 5 years: +8.7% a year against +11.6%.
When is 13D Management LLC's next 13F filing due?
13F filings are due 45 days after each quarter ends. 13D Management LLC's filing for the quarter ending Sep 30, 2026 is due by Nov 14, 2026; this page updates the day after it is published.
How much money does 13D Management LLC manage?
13D Management LLC reported $99.4M of regulatory assets under management on its latest SEC Form ADV. Its 13F, which covers only US-listed stocks and options, totals $71.3M.