Supermicro insider activity
What the executives and directors of Supermicro actually did with their own shares, decoded from their SEC Form 4 filings. Each figure says the stretch of time it covers.
−$19M
net open-market flow, 12 m
0 open-market buys, 12 m
81.6%
of sale value on 10b5-1 plans, 12 m
963 days since an insider bought, whole record
The tape: three years of insider trades
Open-market buy
Discretionary sale
Planned sale (10b5-1)
Reported-price path
Routine
Every marker sits at the price reported on the Form 4. The line is the monthly median of all prices insiders reported, so the chart needs no market feed; the grey strip is the routine flow (grants, vestings, tax withholding and gifts) that a headline gets wrong by counting it as selling. The share count changed 10-for-1 on Oct 1, 2024, so prices and share counts reported before then are restated to today's basis here; otherwise the tape would show a step the shares never took.
The 162 routine events on the chart, as a list
| Date | Insider | Shares |
|---|---|---|
| Aug 17, 2026 | Liu Liang Chiu-Chu Sara | 5,620 |
| Aug 17, 2026 | Liang Charles | 5,620 |
| Aug 17, 2026 | Cheung Kenneth | 3,058 |
| Aug 17, 2026 | WEIGAND DAVID E | 9,808 |
| Aug 17, 2026 | Xiao Jin | 5,436 |
| Aug 17, 2026 | Malyala Vikranth | 9,053 |
| Aug 17, 2026 | Thauberger Matthew | 3,395 |
| Aug 10, 2026 | Liu Liang Chiu-Chu Sara | 4,826 |
| Aug 10, 2026 | Liang Charles | 4,826 |
| Aug 10, 2026 | Cheung Kenneth | 6,359 |
| Aug 10, 2026 | WEIGAND DAVID E | 2,234 |
| Aug 10, 2026 | Xiao Jin | 4,069 |
| Aug 10, 2026 | Malyala Vikranth | 4,902 |
| Aug 10, 2026 | Thauberger Matthew | 1,766 |
| Jul 1, 2026 | Liu Liang Chiu-Chu Sara | 2,485 |
| Jul 1, 2026 | Liang Charles | 2,485 |
| Jul 1, 2026 | WEIGAND DAVID E | 30K |
| Jul 1, 2026 | Malyala Vikranth | 12K |
| Jun 30, 2026 | BLAIR ROBERT L | 5,383 |
| Jun 30, 2026 | LIU TALLY C | 2,691 |
| Jun 30, 2026 | Lin Judy L. | 5,383 |
| Jun 30, 2026 | Mogensen Susan | 5,383 |
| Jun 30, 2026 | Angel Scott | 5,383 |
| Jun 17, 2026 | WEIGAND DAVID E | 6,794 |
| Jun 17, 2026 | Malyala Vikranth | 10K |
| May 26, 2026 | Liu Liang Chiu-Chu Sara | 340K |
| May 26, 2026 | Liang Charles | 340K |
| May 10, 2026 | Liu Liang Chiu-Chu Sara | 9,573 |
| May 10, 2026 | Liang Charles | 9,573 |
| May 10, 2026 | Cheung Kenneth | 1,699 |
| May 10, 2026 | CLEGG DON W | 3,139 |
| May 10, 2026 | WEIGAND DAVID E | 5,667 |
| May 10, 2026 | Xiao Jin | 8,246 |
| Feb 27, 2026 | Liu Liang Chiu-Chu Sara | 21K |
| Feb 27, 2026 | Liang Charles | 21K |
| Feb 17, 2026 | Liaw Yih-Shyan Wally | 4,620 |
| Feb 17, 2026 | Liu Liang Chiu-Chu Sara | 5,758 |
| Feb 17, 2026 | Liang Charles | 5,758 |
| Feb 17, 2026 | Cheung Kenneth | 3,177 |
| Feb 17, 2026 | CLEGG DON W | 2,466 |
| Feb 17, 2026 | WEIGAND DAVID E | 8,833 |
| Feb 17, 2026 | Xiao Jin | 5,534 |
| Feb 10, 2026 | Liaw Yih-Shyan Wally | 13K |
| Feb 10, 2026 | Liu Liang Chiu-Chu Sara | 3,361 |
| Feb 10, 2026 | Liang Charles | 3,361 |
| Feb 10, 2026 | Cheung Kenneth | 1,765 |
| Feb 10, 2026 | CLEGG DON W | 3,263 |
| Feb 10, 2026 | WEIGAND DAVID E | 5,859 |
| Feb 10, 2026 | Xiao Jin | 2,782 |
| Jan 29, 2026 | LIU TALLY C | 747 |
| Nov 26, 2025 | Liu Liang Chiu-Chu Sara | 5,000 |
| Nov 26, 2025 | Liang Charles | 5,000 |
| Nov 24, 2025 | KAO GEORGE | 57K |
| Nov 13, 2025 | KAO GEORGE | 116K |
| Nov 10, 2025 | Liaw Yih-Shyan Wally | 18K |
| Nov 10, 2025 | Liu Liang Chiu-Chu Sara | 3,247 |
| Nov 10, 2025 | Liang Charles | 3,247 |
| Nov 10, 2025 | Cheung Kenneth | 1,885 |
| Nov 10, 2025 | CLEGG DON W | 3,484 |
| Nov 10, 2025 | WEIGAND DAVID E | 6,288 |
Where the shares went, last 12 months
Every Form 4 movement decomposed: what flowed in (grants, vested equity, purchases) and what flowed out (tax withholding, plan sales, discretionary sales, gifts). Counted in shares, because grants carry no price. The share count changed 10-for-1 on Oct 1, 2024, so share counts reported before then are restated to today's basis here.
The chart, in numbers
| Flow | Shares |
|---|---|
| From holdings | 839K |
| Vested / exercised | 468K |
| Withheld for tax | 112K |
| Planned sales (10b5-1) | 400K |
| Discretionary sales | 106K |
| Gifts | 690K |
Skin in the game
Directly held shares as reported after each trade, indexed to 100 at the start of the window, up to five years back. Direct holdings only: trust and family-entity positions are per-entity in the filings and do not sum honestly, so this chart refuses to guess. The steps are the trades. The share count changed 10-for-1 on Oct 1, 2024, so share counts reported before then are restated to today's basis here.
The chart, in numbers
| Insider | Start of the window | Latest reported | Indexed, start = 100 |
|---|---|---|---|
| Liang Charles | 67M | 40M | 60.8 |
| Liu Liang Chiu-Chu Sara | 900K | 438K | 48.6 |
| Liaw Yih-Shyan Wally | 45K | 94K | 208.5 |
| LIU TALLY C | 294K | 289K | 98.2 |
| TUAN SHERMAN | 249K | 207K | 83.2 |
Who holds what
the 14 largest holdings of 18| Insider | Role | Shares held | Buys 12 m | Sales 12 m | 12 m | Last trade |
|---|---|---|---|---|---|---|
| Liang Charles President and CEO Last trade Sep 4, 2026 | CEO | 41M | – | $7.7M | net selling over the year: 0 months buying, 1 month selling | Sep 4, 2026 |
| Liu Liang Chiu-Chu Sara Last trade Sep 4, 2026 | Director | 26M | – | $7.7M | net selling over the year: 0 months buying, 1 month selling | Sep 4, 2026 |
| Liaw Yih-Shyan Wally Last trade Aug 26, 2016 | Director | 15M | – | – | Aug 26, 2016 | |
| LIU TALLY C Last trade May 30, 2024 | Director | 289K | – | – | May 30, 2024 | |
| TUAN SHERMAN Last trade Nov 26, 2025 | Director | 207K | – | $1.6M | net selling over the year: 0 months buying, 1 month selling | Nov 26, 2025 |
| Xiao Jin Sr. Corporate VP, Engineering | Officer | 196K | – | – | – | |
| KAO GEORGE SVP, OPERATIONS Last trade Nov 24, 2025 | Officer | 183K | – | $1.9M | net selling over the year: 0 months buying, 1 month selling | Nov 24, 2025 |
| WEIGAND DAVID E SVP, Chief Financial Officer Last trade Sep 15, 2025 | CFO | 138K | – | – | Sep 15, 2025 | |
| Cheung Kenneth SVP, Chief Accounting Officer | Officer | 65K | – | – | – | |
| Lin Judy L. Last trade Feb 16, 2023 | Director | 60K | – | – | Feb 16, 2023 | |
| Malyala Vikranth SVP, Chief Business Officer | Officer | 51K | – | – | – | |
| CLEGG DON W SVP, Worldwide Sales Last trade Feb 14, 2024 | Officer | 50K | – | – | Feb 14, 2024 | |
| CHAN SHIU LEUNG Last trade Feb 1, 2024 | Director | 43K | – | – | Feb 1, 2024 | |
| FAIRFAX DANIEL W Last trade Jun 3, 2024 | Director | 20K | – | – | Jun 3, 2024 |
Open-market trade log
the 60 most recent of 642| Date | Insider | Type | Shares | Price | Value | Since trade | Filed |
|---|---|---|---|---|---|---|---|
| Sep 4, 2026 | Liu Liang Chiu-Chu Sara (Director) 100K shares $40.00 −6.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 100K | $40.00 | $4.0M | −6.0% | Sep 8, 2026 |
| Sep 4, 2026 | Liang Charles (CEO) 100K shares $40.00 −6.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 100K | $40.00 | $4.0M | −6.0% | Sep 8, 2026 |
| Sep 3, 2026 | Liu Liang Chiu-Chu Sara (Director) 43K shares $36.60 +2.8% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 43K | $36.60 | $1.6M | +2.8% | Sep 8, 2026 |
| Sep 3, 2026 | Liu Liang Chiu-Chu Sara (Director) 57K shares $37.62 +0.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 57K | $37.62 | $2.2M | +0.0% | Sep 8, 2026 |
| Sep 3, 2026 | Liang Charles (CEO) 43K shares $36.60 +2.8% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 43K | $36.60 | $1.6M | +2.8% | Sep 8, 2026 |
| Sep 3, 2026 | Liang Charles (CEO) 57K shares $37.62 +0.0% since trade filed Sep 8, 2026 | Planned sale (10b5-1) | 57K | $37.62 | $2.2M | +0.0% | Sep 8, 2026 |
| Nov 26, 2025 | TUAN SHERMAN (Director) 49K shares $33.00 +14.0% since trade filed Dec 1, 2025 | Discretionary sale | 49K | $33.00 | $1.6M | +14.0% | Dec 1, 2025 |
| Nov 24, 2025 | KAO GEORGE (Officer) 57K shares $32.83 +14.6% since trade filed Nov 26, 2025 | Discretionary sale | 57K | $32.83 | $1.9M | +14.6% | Nov 26, 2025 |
| Sep 15, 2025 | WEIGAND DAVID E (CFO) 25K shares $45.14 −16.7% since trade filed Sep 17, 2025 | Planned sale (10b5-1) | 25K | $45.14 | $1.1M | −16.7% | Sep 17, 2025 |
| Sep 3, 2025 | WEIGAND DAVID E (CFO) 300 shares $40.85 −7.9% since trade filed Sep 5, 2025 | Planned sale (10b5-1) | 300 | $40.85 | $12K | −7.9% | Sep 5, 2025 |
| Sep 3, 2025 | WEIGAND DAVID E (CFO) 25K shares $40.28 −6.6% since trade filed Sep 5, 2025 | Planned sale (10b5-1) | 25K | $40.28 | $995K | −6.6% | Sep 5, 2025 |
| Aug 22, 2025 | KAO GEORGE (Officer) 40K shares $43.88 −14.3% since trade filed Aug 26, 2025 | Discretionary sale | 40K | $43.88 | $1.8M | −14.3% | Aug 26, 2025 |
| Jul 28, 2025 | Liu Liang Chiu-Chu Sara (Director) 200K shares $60.00 −37.3% since trade filed Jul 30, 2025 | Planned sale (10b5-1) | 200K | $60.00 | $12M | −37.3% | Jul 30, 2025 |
| Jul 28, 2025 | Liang Charles (CEO) 200K shares $60.00 −37.3% since trade filed Jul 30, 2025 | Planned sale (10b5-1) | 200K | $60.00 | $12M | −37.3% | Jul 30, 2025 |
| Jun 18, 2025 | Liu Liang Chiu-Chu Sara (Director) 300K shares $45.00 −16.4% since trade filed Jun 20, 2025 | Planned sale (10b5-1) | 300K | $45.00 | $14M | −16.4% | Jun 20, 2025 |
| Jun 18, 2025 | Liang Charles (CEO) 300K shares $45.00 −16.4% since trade filed Jun 20, 2025 | Planned sale (10b5-1) | 300K | $45.00 | $14M | −16.4% | Jun 20, 2025 |
| May 20, 2025 | WEIGAND DAVID E (CFO) 67K shares $44.02 −14.5% since trade filed May 22, 2025 | Discretionary sale | 67K | $44.02 | $2.9M | −14.5% | May 22, 2025 |
| May 14, 2025 | Liu Liang Chiu-Chu Sara (Director) 15K shares $45.56 −17.4% since trade filed May 16, 2025 | Discretionary sale | 15K | $45.56 | $697K | −17.4% | May 16, 2025 |
| May 14, 2025 | Liu Liang Chiu-Chu Sara (Director) 185K shares $44.98 −16.4% since trade filed May 16, 2025 | Discretionary sale | 185K | $44.98 | $8.3M | −16.4% | May 16, 2025 |
| May 14, 2025 | Liang Charles (CEO) 15K shares $44.56 −15.6% since trade filed May 16, 2025 | Discretionary sale | 15K | $44.56 | $682K | −15.6% | May 16, 2025 |
| May 14, 2025 | Liang Charles (CEO) 185K shares $44.98 −16.4% since trade filed May 16, 2025 | Discretionary sale | 185K | $44.98 | $8.3M | −16.4% | May 16, 2025 |
| May 14, 2025 | KAO GEORGE (Officer) 28K shares $45.86 −18.0% since trade filed May 16, 2025 | Discretionary sale | 28K | $45.86 | $1.3M | −18.0% | May 16, 2025 |
| Feb 28, 2025 | BLAIR ROBERT L (Director) 5,860 shares $42.85 −12.2% since trade filed Mar 4, 2025 | Discretionary sale | 5,860 | $42.85 | $251K | −12.2% | Mar 4, 2025 |
| Feb 28, 2025 | BLAIR ROBERT L (Director) 14K shares $42.46 −11.4% since trade filed Mar 4, 2025 | Discretionary sale | 14K | $42.46 | $577K | −11.4% | Mar 4, 2025 |
| Feb 26, 2025 | Liu Liang Chiu-Chu Sara (Director) 46K shares $50.17 −25.0% since trade filed Feb 28, 2025 | Discretionary sale | 46K | $50.17 | $2.3M | −25.0% | Feb 28, 2025 |
| Feb 26, 2025 | Liang Charles (CEO) 46K shares $50.17 −25.0% since trade filed Feb 28, 2025 | Discretionary sale | 46K | $50.17 | $2.3M | −25.0% | Feb 28, 2025 |
| Feb 26, 2025 | KAO GEORGE (Officer) 72K shares $50.48 −25.5% since trade filed Feb 28, 2025 | Discretionary sale | 72K | $50.48 | $3.6M | −25.5% | Feb 28, 2025 |
| Jun 3, 2024 | FAIRFAX DANIEL W (Director) 300 shares $802.00 −53.1% since trade filed Jun 5, 2024 | Planned sale (10b5-1) | 300 | $802.00 | $241K | −53.1% | Jun 5, 2024 |
| May 30, 2024 | LIU TALLY C (Director) 500 shares $839.17 −55.2% since trade filed Jun 3, 2024 | Discretionary sale | 500 | $839.17 | $420K | −55.2% | Jun 3, 2024 |
| May 1, 2024 | FAIRFAX DANIEL W (Director) 300 shares $777.36 −51.6% since trade filed May 3, 2024 | Planned sale (10b5-1) | 300 | $777.36 | $233K | −51.6% | May 3, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 14 shares $891.07 −57.8% since trade filed May 1, 2024 | Discretionary sale | 14 | $891.07 | $12K | −57.8% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 15 shares $831.02 −54.7% since trade filed May 1, 2024 | Discretionary sale | 15 | $831.02 | $12K | −54.7% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 15 shares $837.01 −55.1% since trade filed May 1, 2024 | Discretionary sale | 15 | $837.01 | $13K | −55.1% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $835.87 −55.0% since trade filed May 1, 2024 | Discretionary sale | 16 | $835.87 | $13K | −55.0% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $841.64 −55.3% since trade filed May 1, 2024 | Discretionary sale | 16 | $841.64 | $13K | −55.3% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $843.13 −55.4% since trade filed May 1, 2024 | Discretionary sale | 16 | $843.13 | $13K | −55.4% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $848.01 −55.6% since trade filed May 1, 2024 | Discretionary sale | 16 | $848.01 | $14K | −55.6% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $858.49 −56.2% since trade filed May 1, 2024 | Discretionary sale | 16 | $858.49 | $14K | −56.2% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $864.56 −56.5% since trade filed May 1, 2024 | Discretionary sale | 16 | $864.56 | $14K | −56.5% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $866.60 −56.6% since trade filed May 1, 2024 | Discretionary sale | 16 | $866.60 | $14K | −56.6% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $872.30 −56.9% since trade filed May 1, 2024 | Discretionary sale | 16 | $872.30 | $14K | −56.9% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $873.50 −56.9% since trade filed May 1, 2024 | Discretionary sale | 16 | $873.50 | $14K | −56.9% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $878.14 −57.2% since trade filed May 1, 2024 | Discretionary sale | 16 | $878.14 | $14K | −57.2% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $879.55 −57.2% since trade filed May 1, 2024 | Discretionary sale | 16 | $879.55 | $14K | −57.2% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $888.40 −57.7% since trade filed May 1, 2024 | Discretionary sale | 16 | $888.40 | $14K | −57.7% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 16 shares $892.50 −57.9% since trade filed May 1, 2024 | Discretionary sale | 16 | $892.50 | $14K | −57.9% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 19 shares $839.72 −55.2% since trade filed May 1, 2024 | Discretionary sale | 19 | $839.72 | $16K | −55.2% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 30 shares $894.17 −57.9% since trade filed May 1, 2024 | Discretionary sale | 30 | $894.17 | $27K | −57.9% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $854.89 −56.0% since trade filed May 1, 2024 | Discretionary sale | 32 | $854.89 | $27K | −56.0% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $869.83 −56.8% since trade filed May 1, 2024 | Discretionary sale | 32 | $869.83 | $28K | −56.8% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $875.35 −57.0% since trade filed May 1, 2024 | Discretionary sale | 32 | $875.35 | $28K | −57.0% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $877.35 −57.1% since trade filed May 1, 2024 | Discretionary sale | 32 | $877.35 | $28K | −57.1% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $883.04 −57.4% since trade filed May 1, 2024 | Discretionary sale | 32 | $883.04 | $28K | −57.4% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $887.19 −57.6% since trade filed May 1, 2024 | Discretionary sale | 32 | $887.19 | $28K | −57.6% | May 1, 2024 |
| Apr 29, 2024 | Liu Liang Chiu-Chu Sara (Director) 32 shares $889.69 −57.7% since trade filed May 1, 2024 | Discretionary sale | 32 | $889.69 | $28K | −57.7% | May 1, 2024 |
| Apr 29, 2024 | Liang Charles (CEO) 14 shares $891.07 −57.8% since trade filed May 1, 2024 | Discretionary sale | 14 | $891.07 | $12K | −57.8% | May 1, 2024 |
| Apr 29, 2024 | Liang Charles (CEO) 15 shares $831.02 −54.7% since trade filed May 1, 2024 | Discretionary sale | 15 | $831.02 | $12K | −54.7% | May 1, 2024 |
| Apr 29, 2024 | Liang Charles (CEO) 15 shares $837.01 −55.1% since trade filed May 1, 2024 | Discretionary sale | 15 | $837.01 | $13K | −55.1% | May 1, 2024 |
| Apr 29, 2024 | Liang Charles (CEO) 16 shares $835.87 −55.0% since trade filed May 1, 2024 | Discretionary sale | 16 | $835.87 | $13K | −55.0% | May 1, 2024 |
| Apr 29, 2024 | Liang Charles (CEO) 16 shares $841.64 −55.3% since trade filed May 1, 2024 | Discretionary sale | 16 | $841.64 | $13K | −55.3% | May 1, 2024 |
“Since trade” compares with the latest insider-implied price, not a market quote: these pages are built from filings alone. A role here is the one on that day's Form 4, so somebody promoted since appears under both titles. The share count changed 10-for-1 on Oct 1, 2024. This table prints prices and share counts as they were filed, on the basis of the day, while the charts above are on today's; “Since trade” puts the filed price on today's basis first, which is why it does not divide into the price beside it.
Filing hygiene
257 Forms 4, 3 years
0 filed late
1 amendments
2 avg. days to file
How to read this
A Form 4 transaction code decides everything. P is an open-market purchase and S an open-market sale; those two are the only codes where an insider chose to trade. A is a grant, M an option exercise or vesting, F shares withheld to cover tax, G a gift. Most “insiders dumped billions” headlines are code F and M mechanics.
Sales flagged 10b5-1 run on a plan the insider adopted in advance; since 2023 every Form 4 carries that flag. Buys have historically predicted returns, sales mostly have not, and this page states filings, not advice.