Latest filingSep 09, 2026Most recent Form 4
CBRS
Cerebras Systems Inc.
NasdaqTechnologySemiconductors & Related Devices
Insider activity for last month from 08/09 to 09/09. Counts use processed Form 4 rows. Purchase and sale metrics use codes P and S; totals remain unknown when any matching value is missing. Rows without a usable transaction date cannot be assigned to a rolling period and are excluded.
Total buying$00 buys
Total selling$22.7B145 sells
Net open-market-$22.7B22 insiders
Open-market mix
Buy vs sell distribution by transaction countInsider activity report
Monthly open-market purchase and sale counts Buys Sells
Transaction codes
By Form 4 transaction code in selected period247transactions
- S · Open-market sells · dominant145 · 59%
- C · Code C46 · 19%
- J · Other42 · 17%
- M · Option exercise12 · 5%
- G · Gifts2 · 1%
Activity by reported role
A joint filing can contribute to multiple roles297transactions
- CTO · dominant58 · 20%
- Director51 · 17%
- Chief executive officer50 · 17%
- PRES50 · 17%
- 10% owner31 · 10%
- COO28 · 9%
- CAO27 · 9%
- Chief financial officer2 · 1%
Distinct insiders active
Reporting-owner CIKs by month · peak Aug 2026 (22)Aug 2026Sep 2026
Reported Holdings After
Separated by insider, security, and ownership typeLie SeanClass A Common Stock · Direct
415,067Sep 04, 2026
Mallick DhirajClass A Common Stock · Direct
158,889Aug 18, 2026
Patel YagneshClass A Common Stock · Direct
18,776Aug 18, 2026
Feldman Andrew D.Class A Common Stock · Direct
49,694Sep 04, 2026
Lie SeanClass B Common Stock · Direct
7,629,133Sep 04, 2026
Lie SeanStock Option · Direct
289,021Sep 04, 2026
Vassallo StevenClass A Common Stock · Indirect · By Revocable Trust
179,087Sep 04, 2026
Foundation Capital Management Co. VIII, L.L.C.Class A Common Stock · Indirect · By Foundation Capital Management Co. LF II, L.L.C.
0Aug 18, 2026
These are reported post-transaction holdings, not company-wide ownership percentages. Securities, indirect vehicles, and amendments are kept separate.
Filing activity heatmap
Each cell is one day · intensity = transactions · buys green, sells redAug 09 → Sep 09
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Top insiders
By absolute net value across the selected period- LS-$150.1M
- VS-$10.5M
- FD-$7.9M
Recent filing activity
Most recent 12 transactions · color = transaction codeFiling detail checks
Secondary metrics for the selected periodFiling-only signals
Deterministic matches in the selected period
CBRS transaction history
Filters apply within this company and selected period by default| Ticker | Insider | Role | Type | Shares | Value | Code | Signals | 90d return | Filed | Trans date |
|---|---|---|---|---|---|---|---|---|---|---|
| CBRS | Vassallo Steven | DIR | sale | 7.11k | -$150M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Vassallo Steven | DIR | sale | 21.7k | -$458M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Vassallo Steven | DIR | sale | 21.1k | -$443M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | unknown10b5-1 | 46.1k | $0 | C | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 46.1k | $0 | M | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 46.1k | $0 | M | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | sale10b5-1 | 53.4k | -$1.12B | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | gift10b5-1 | 16.0k | $0 | G | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | unknown10b5-1 | 46.1k | — | C | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | unknown10b5-1 | 37.4k | $0 | C | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | exercise10b5-1 | 37.4k | $0 | M | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | exercise10b5-1 | 37.4k | $0 | M | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | other10b5-1 | 120 | $0 | J | — | 0.0% | 09/09 | 09/08 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 100 | -$2.16M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 600 | -$12.9M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 1.40k | -$30.0M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 3.89k | -$83.3M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 3.32k | -$70.8M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 7.43k | -$157M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 6.15k | -$129M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 6.72k | -$141M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 1.70k | -$35.6M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 1.50k | -$31.1M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 800 | -$16.5M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 1.20k | -$24.4M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 900 | -$18.2M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 300 | -$6.05M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 300 | -$6.02M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | sale10b5-1 | 1.10k | -$21.9M | S | — | 0.0% | 09/09 | 09/04 |
| CBRS | Feldman Andrew D. | CEOPRES | unknown10b5-1 | 37.4k | $0 | C | — | 0.0% | 09/09 | 09/04 |
| CBRS | Lie Sean | CTO | unknown10b5-1 | 16.2k | $0 | C | −8.7% | 08/22 | 08/21 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 16.2k | $0 | M | −8.7% | 08/22 | 08/21 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 16.2k | $0 | M | −8.7% | 08/22 | 08/21 | |
| CBRS | Lie Sean | CTO | unknown10b5-1 | 696k | $0 | C | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 696k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 48.5k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 114k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 87.3k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 138k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | exercise10b5-1 | 308k | $0 | M | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 16.2k | -$342M | S | −8.7% | 08/22 | 08/21 | |
| CBRS | Lie Sean | CTO | unknown10b5-1 | 16.2k | $0 | C | −8.7% | 08/22 | 08/21 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 24.6k | -$524M | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 10.7k | -$226M | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 46.2k | -$973M | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 114k | -$2.41B | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 119k | -$2.48B | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 108k | -$2.25B | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 93.0k | -$1.92B | S | −8.7% | 08/22 | 08/20 | |
| CBRS | Lie Sean | CTO | sale10b5-1 | 133k | -$2.74B | S | −8.7% | 08/22 | 08/20 |
Cerebras Systems Inc. Insider Activity FAQ
SEC Form 4 contextWho recently reported transactions at Cerebras Systems Inc.?
Vassallo Steven, Lie Sean, Feldman Andrew D., Vishria Eric, Benchmark Capital Management Co. IX, L.L.C., Benchmark Capital Management Co. VIII, L.L.C., Benchmark Capital Partners IX, L.P., Benchmark Capital Partners VIII, L.P., Benchmark Founders' Fund IX-A, L.P., Benchmark Founders' Fund IX-B, L.P., Benchmark Founders' Fund IX, L.P., Benchmark Founders' Fund VIII-B, L.P..
When was the latest reported open-market purchase?
No code-P purchase is available for this period.
When was the latest reported open-market sale?
Vassallo Steven reported a sale on Sep 04, 2026 valued at $150M. Read the SEC filing.
What is the recent purchase and sale balance?
Net open-market selling in the selected period was $227,578,722.44. Sales can occur for many non-investment reasons.
Where can I see the original SEC filing?
Every transaction row and latest-activity fact links to its original SEC filing.
What do these Form 4 transaction codes mean?
P and S generally describe open-market or private purchases and sales. A, D, F, M, X, G, J, and V describe awards, issuer dispositions, tax withholding, exercises, gifts, other transactions, and voluntary early reports; review each filing and its footnotes for context.