Atom Investors LP
- SEC CIK
- 0001738902
- Latest filing
- Aug 14, 2026
The latest 13F from Atom Investors LP covers Q2 2026 (filed Aug 14, 2026): 818 long positions worth $1.12B. The top 10 holdings make up 11.0% of the portfolio, and the largest is Vanguard S&P 500 ETF at 4.1%. Livermore has 22 filings on Form 13F from this institution, going back to Q1 2021.
What changed in Q2 2026
Share counts compared with Q1 2026: how many positions were new, added to, reduced or sold out, and the biggest buys and sells. Dollar amounts are estimated at the quarter-end prices implied by the filing.
- New
- 417
- Est. +$456.3M
- Added
- 145
- Est. +$143.9M
- Reduced
- 253
- Est. −$541.3M
- Sold out
- 240
- Est. −$440.1M
Top 5 holdings
Share of this quarter's portfolio value
Biggest buys
New and added positions, by estimated amount bought
Largest weight increases
New and added positions, by percentage points of the portfolio gained
Biggest sells
Reduced and sold-out positions, by estimated amount sold
Largest weight decreases
Reduced and sold-out positions, by percentage points of the portfolio lost
Metrics
13F metrics for Q2 2026, computed only from the numbers in the filings. Definitions below.
- Portfolio value
- $1.12B
- −$272.4M (−19.5%) vs. prior quarter
- Positions
- 818
- +177 vs. prior quarter
- Top 10 concentration
- 11.0%
- Top 10 as share of value
- Turnover
- 47.6%
- Q2 2026, one quarter
- Average holding period
- 2.6 quarters
- Weighted by value
How these are calculated
- Portfolio value: the market value of all long positions in the 13F, as reported at quarter end, excluding options.
- Top 10 concentration: the combined value of the 10 largest positions as a share of portfolio value.
- Turnover: the smaller of this quarter's estimated purchases and estimated sales, divided by the average of this and last quarter's portfolio value. Estimates multiply the change in shares by the quarter-end price implied by the filing (market value divided by shares); new positions use this quarter's value and sold-out positions last quarter's. Only positions reported in shares count, and it is not calculated when the previous quarter was not filed.
- Average holding period: how many consecutive quarters each current position has been held (including this one; a quarter without the position or without a filing starts the count over), weighted by this quarter's value. Counting starts with the first 13F in Livermore (Q1 2021), so positions held before then are understated.
13F filings by quarter
22 quarters, going back to Q1 2021. Bars show each quarter's 13F portfolio value; quarters without a filing are left blank.
Peak $1.40B (Q1 2026)
| Quarter | Filed | Positions | Value | Top 3 holdings | Changes | Filing |
|---|---|---|---|---|---|---|
| Q2 2026 | Aug 14, 2026 | 818 | $1.12B | Vanguard S&P 500 ETFVTRSINTC | vs. Q1 2026 | SEC |
| Q1 2026 | May 15, 2026 | 641 | $1.40B | Vanguard S&P 500 ETFTECHEQIX | vs. Q4 2025 | SEC |
| Q4 2025 | Feb 17, 2026 | 556 | $1.26B | Vanguard S&P 500 ETFTECHSITE | vs. Q3 2025 | SEC |
| Q3 2025 | Nov 14, 2025 | 584 | $1.32B | iShares Russell 2000 ETFSPYiShares Tr | vs. Q2 2025 | SEC |
| Q2 2025 | Aug 14, 2025 | 587 | $1.13B | iShares Russell 2000 ETFiShares TrState Street Financial Select Sector SPDR ETF | vs. Q1 2025 | SEC |
| Q1 2025 | May 15, 2025 | 488 | $812.9M | iShares TrState Street Financial Select Sector SPDR ETFAWK | vs. Q4 2024 | SEC |
| Q4 2024 | Feb 14, 2025 | 481 | $805.0M | iShares Russell 2000 ETFiShares TrAWK | vs. Q3 2024 | SEC |
| Q3 2024 | Nov 14, 2024 | 456 | $955.2M | iShares TrMSFTAXTA | vs. Q2 2024 | SEC |
| Q2 2024 | Aug 14, 2024 | 457 | $1.00B | iShares TrBACTSM | vs. Q1 2024 | SEC |
| Q1 2024 | May 15, 2024 | 563 | $795.8M | iShares Russell 2000 ETFSPYHON | vs. Q4 2023 | SEC |
| Q4 2023 | Feb 14, 2024 | 439 | $566.2M | iShares Russell 2000 ETFSPYHON | vs. Q3 2023 | SEC |
| Q3 2023 | Nov 14, 2023 | 421 | $438.6M | iShares TriShares Russell 2000 ETFSPY | vs. Q2 2023 | SEC |
| Q2 2023 | Aug 14, 2023 | 280 | $263.3M | iShares TriShares Russell 2000 ETFSPY | vs. Q1 2023 | SEC |
| Q1 2023 | May 15, 2023 | 247 | $183.8M | iShares TrState Street SPDR S&P Biotech ETFState Street Health Care Select Sector SPDR ETF | vs. Q4 2022 | SEC |
| Q4 2022 | Feb 14, 2023 | 216 | $200.1M | State Street SPDR S&P Biotech ETFiShares TrState Street SPDR S&P Regional Banking ETF | vs. Q3 2022 | SEC |
| Q3 2022 | Nov 8, 2022 | 274 | $284.3M | State Street SPDR S&P Biotech ETFiShares TrMSFT | vs. Q2 2022 | SEC |
| Q2 2022 | Aug 15, 2022 | 246 | $228.7M | State Street Health Care Select Sector SPDR ETFState Street SPDR S&P Biotech ETFiShares Tr | vs. Q1 2022 | SEC |
| Q1 2022 | May 16, 2022 | 185 | $213.8M | iShares TrState Street Health Care Select Sector SPDR ETFState Street SPDR S&P Biotech ETF | vs. Q4 2021 | SEC |
| Q4 2021 | Feb 14, 2022 | 247 | $362.6M | iShares TrState Street SPDR S&P Biotech ETFState Street Health Care Select Sector SPDR ETF | vs. Q3 2021 | SEC |
| Q3 2021 | Nov 15, 2021 | 283 | $512.7M | State Street SPDR S&P Biotech ETFiShares TrSPY | vs. Q2 2021 | SEC |
| Q2 2021 | Aug 16, 2021 | 222 | $479.8M | iShares TrState Street SPDR S&P Biotech ETFState Street Health Care Select Sector SPDR ETF | vs. Q1 2021 | SEC |
| Q1 2021 | May 17, 2021 | 225 | $543.2M | iShares Russell 2000 ETFState Street Health Care Select Sector SPDR ETFSPY | – | SEC |