ARK Invest adds $19.6M to Cerebras Systems Inc while it sinks 20%
The buying came from ARKK and ARKW, right as the stock slid. Plus the other trades that day and how ARK compares with the market.
Generated from ARK's own holdings data.
ARK Invest's ARK Invest bought an estimated $19.6M of Cerebras Systems Inc (CBRS) on 5 Oct 2026, through ARKK and ARKW. The stock was 20% cheaper than a week earlier when the order went through.
Every other holding grew by about 3.5% that day as money came into the funds. This position grew by 14% — the gap is what makes it a deliberate trade rather than cash being spread across the portfolio.
This isn't a one-off. Across 3 trades in 30 days, ARK has bought a net $26.1M of the stock.
Everything ARK did on 5 Oct 2026
ARK made 7 real moves that day, once money flowing in and out of the funds is stripped out:
| Stock | Funds | Est. value |
|---|---|---|
| CBRS Cerebras Systems IncBought after a 20% drop this week | ARKK and ARKW | +$19.6M |
| BWXT Bwx Technologies Inc | ARKK | +$9.8M |
| NTLA Intellia Therapeutics IncBought 4 days running | ARKG and ARKK | +$4.9M |
| AMZN Amazon.Com Inc | ARKW | +$4.2M |
| ABNB Airbnb Inc | ARKF | +$2.6M |
| DASH Doordash Inc | ARKF | +$2.2M |
The bigger picture: ARK's last 30 days
Over the last 30 days ARK's biggest net buys have been Nvidia Corp ($81.0M), Meta Platforms Inc ($73.6M), Rocket Lab ($42.3M). Going the other way: Advanced Micro Devices ($130.3M), 10X Genomics Inc ($75.6M), Alphabet Inc ($36.4M) have been cut.
Is it working?
This year ARKK is ahead of the market — +16.8% against +13.7% for the S&P 500.
It has been a strong month: ARKK is +7.7% against +0.8% for the S&P 500, helped most by Twist Bioscience Corp (+47%, 3% of the fund), 10X Genomics Inc (+48%, 3% of the fund), Tempus AI Inc (+19%, 5% of the fund).
Over the past year the gap is wider: ARKK returned +0.7% against +16.2% for the S&P 500, 16 points apart.
That five-year gap — 107 points — mostly comes down to timing. Five years ago ARKK was trading close to its all-time high of Feb 2021. It then fell 81% to its low in Dec 2022, and it is still 42% below that peak today. Any comparison that starts near the top of that boom looks brutal.
| To date | 1 month | YTD | 1 year | 5 years |
|---|---|---|---|---|
| ARKK | +7.7% | +16.8% | +0.7% | -17.8% |
| S&P 500 (SPY) | +0.8% | +13.7% | +16.2% | +89.5% |
| Nasdaq-100 (QQQ) | +5.8% | +22.3% | +24.2% | +114.2% |
How we work this out
ETFpeek is an independent research tool and is not affiliated with ARK Invest or Cathie Wood. Figures are estimates from public fund data, shown for information only — not financial advice. Past performance does not indicate future results.