Insider · CIK 0001421563
Robert Gardner Harrison
Files at SERA (SERA PROGNOSTICS, INC.). First filing Nov 12, 2024, latest Mar 12, 2026.
Robert Gardner Harrison files SEC Form 4 as officer at SERA (SERA PROGNOSTICS, INC.). Since Nov 12, 2024, Robert Gardner Harrison has reported 0 open-market buys worth $0 and 23 open-market sells worth $351k, the latest filed on Mar 12, 2026.
A track record needs three past buys with six months of prices behind them; Robert Gardner Harrison has 0, so none is measured yet.
The newest scored trade: sold $1,461 of SERA on Mar 11, 2026, filed Mar 12, 2026, scored 30 (weak). In the last 12 months: 0 buys worth $0 and 9 sells worth $56k.
Where the trades landed
Last year at the company this insider has traded most, with each buy and sell on the bar it happened.
SERA: SERA PROGNOSTICS, INC.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value. Click a marked bar to open the signal.Charts by TradingView Lightweight Charts™
Signals
This insider’s open-market buys and sells, scored.
| Score | Company | Value | Holdings | Price context | Filed |
|---|---|---|---|---|---|
| 30Weak | SERA PROGNOSTICS, INC. | $1,461 716 shares | -1% | +30% from low-55% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $6,586 3,360 shares | -4% | +30% from low-55% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $4,680 2,000 shares | -2% | +51% from low-48% from high | |
| 0Weak | SERA PROGNOSTICS, INC. | $5,940 2,000 shares | -2% | +101% from low-55% from high | |
| 0Weak | SERA PROGNOSTICS, INC. | $6,000 2,000 shares | -2% | +95% from low-65% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $2,039 616 shares | -1% | +128% from low-61% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $5,860 2,000 shares | -2% | +95% from low-67% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $17k 6,528 shares | -7% | +71% from low-71% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $6,140 2,000 shares | -2% | +103% from low-66% from high | |
| 3Weak | SERA PROGNOSTICS, INC. | $6,360 2,000 shares | -2% | +118% from low-63% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $2,019 645 shares | -1% | +106% from low-65% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $6,100 2,000 shares | -2% | +108% from low-65% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $13k 6,000 shares | -6% | +51% from low-74% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $15k 5,962 shares | -5% | +66% from low-72% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $987 667 shares | -1% | 0% from low-83% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $16k 6,551 shares | -5% | 0% from low-76% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $16k 3,874 shares | -3% | +10% from low-51% from high | |
| 30Weak | SERA PROGNOSTICS, INC. | $14k 3,251 shares | -3% | +6% from low-53% from high | |
| 36Weak | SERA PROGNOSTICS, INC. | $33k 7,297 shares | -6% | +6% from low-51% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $15k 3,610 shares | -3% | +6% from low-51% from high | |
| 10Weak | SERA PROGNOSTICS, INC. | $2,199 554 shares | -0% | 0% from low-54% from high | |
| 25Weak | SERA PROGNOSTICS, INC. | $120k 16,473 shares | -13% | +15% from low-21% from high | |
| 36Weak | SERA PROGNOSTICS, INC. | $35k 4,727 shares | -3% | - |
Planned sales
Form 144 notices this insider filed before selling restricted or control stock, newest first.
| Filed | Company | Shares | Value | Sale date | Past 3 months |
|---|---|---|---|---|---|
| Dec 30, 2025 | SERA SERA PROGNOSTICS, INC. | 2,000 0.01% of outstanding | $6,540 | Dec 30, 2025 | $38k |
| Dec 11, 2025 | SERA Sera Prognostics, Inc. | 616 0.00% of outstanding | $2,037 | Dec 10, 2025 | $38k |
| Dec 2, 2025 | SERA SERA PROGNOSTICS INC | 2,000 0.01% of outstanding | $6,420 | Dec 2, 2025 | $38k |
| Nov 12, 2025 | SERA Sera Prognostics, Inc. | 6,528 0.02% of outstanding | $17k | Nov 10, 2025 | $34k |
| Nov 4, 2025 | SERA SERA PROGNOSTICS, INC. | 2,000 0.01% of outstanding | $6,400 | Nov 4, 2025 | $43k |
| Oct 7, 2025 | SERA SERA PROGNOSTICS, INC. | 2,000 0.01% of outstanding | $6,520 | Oct 7, 2025 | $37k |
| Sep 12, 2025 | SERA Sera Prognostics, Inc. | 645 0.00% of outstanding | $2,018 | Sep 11, 2025 | $35k |
| Sep 9, 2025 | SERA SERA PROGNOSTICS INC | 2,000 0.01% of outstanding | $6,340 | Sep 9, 2025 | $29k |
| Aug 20, 2025 | SERA SERA PROGNOSTICS INC | 6,000 0.02% of outstanding | $14k | Aug 20, 2025 | $16k |
| Aug 11, 2025 | SERA Sera Prognostics, Inc. | 5,962 0.02% of outstanding | $15k | Aug 8, 2025 | $17k |
| Jun 11, 2025 | SERA Sera Prognostics, Inc. | 667 0.00% of outstanding | $990 | Jun 10, 2025 | $16k |
| May 9, 2025 | SERA Sera Prognostics, Inc. | 6,551 0.02% of outstanding | $16k | May 8, 2025 | $78k |
| Mar 7, 2025 | SERA Sera Prognostics, Inc. | 3,251 0.01% of outstanding | $14k | Mar 6, 2025 | $171k |
| Mar 7, 2025 | SERA SERA PROGNOSTICS, INC. | 3,874 0.01% of outstanding | $16k | Mar 7, 2025 | $171k |
| Feb 14, 2025 | SERA Sera Prognostics, Inc. | 7,297 0.02% of outstanding | $33k | Feb 12, 2025 | $157k |
| Feb 13, 2025 | SERA SERA PROGNOSTICS INC | 3,610 0.01% of outstanding | $15k | Feb 13, 2025 | $122k |
| Feb 11, 2025 | SERA SERA PROGNOSTICS INC | 554 0.00% of outstanding | $2,465 | Feb 11, 2025 | $120k |
| Jan 10, 2025 | SERA SERA PROGNOSTICS INC | 16,473 0.05% of outstanding | $137k | Jan 10, 2025 | $35k |
| Nov 13, 2024 | SERA Sera Prognostics, Inc. | 4,727 0.01% of outstanding | $35k | Nov 11, 2024 | none |
Transactions
Every row this insider has filed, 27 in all, newest first.
| Date | Company | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|---|
| Mar 11, 2026 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -716 | $2.04 | $1,461 | 76,712 | Mar 12, 2026 |
| Mar 9, 2026 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -3,360 | $1.96 | $6,586 | 77,428 | Mar 10, 2026 |
| Feb 24, 2026 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $2.34 | $4,680 | 80,788 | Feb 24, 2026 |
| Jan 27, 2026 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $2.97 | $5,940 | 82,788 | Jan 27, 2026 |
| Dec 30, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $3.00 | $6,000 | 84,788 | Dec 30, 2025 |
| Dec 10, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -616 | $3.31 | $2,039 | 86,788 | Dec 11, 2025 |
| Dec 2, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $2.93 | $5,860 | 87,404 | Dec 3, 2025 |
| Nov 10, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -6,528 | $2.62 | $17k | 89,404 | Nov 12, 2025 |
| Nov 4, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $3.07 | $6,140 | 95,932 | Nov 4, 2025 |
| Oct 7, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $3.18 | $6,360 | 97,932 | Oct 8, 2025 |
| Sep 11, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -645 | $3.13 | $2,019 | 99,932 | Sep 12, 2025 |
| Sep 9, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,000 | $3.05 | $6,100 | 100,577 | Sep 9, 2025 |
| Aug 20, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -6,000 | $2.22 | $13k | 102,577 | Aug 20, 2025 |
| Aug 8, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -5,962 | $2.54 | $15k | 108,577 | Aug 11, 2025 |
| Jun 10, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -667 | $1.48 | $987 | 114,539 | Jun 11, 2025 |
| May 8, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -6,551 | $2.44 | $16k | 115,206 | May 9, 2025 |
| Mar 7, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -3,874 | $4.16 | $16k | 121,757 | Mar 10, 2025 |
| Mar 5, 2025 | SERA SERA PROGNOSTICS, INC. | AGrant or award Class A Common Stock | +25,770 | $0.00 | $0 | 128,882 | Mar 7, 2025 |
| Mar 6, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -3,251 | $4.16 | $14k | 125,631 | Mar 7, 2025 |
| Mar 5, 2025 | SERA SERA PROGNOSTICS, INC. | AGrant or award Stock Option (right to buy)derivative | +36,830 | $0.00 | $0 | 36,830 | Mar 7, 2025 |
| Feb 13, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -3,610 | $4.28 | $15k | 103,112 | Feb 14, 2025 |
| Feb 12, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -7,297 | $4.58 | $33k | 106,722 | Feb 14, 2025 |
| Feb 11, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -554 | $3.97 | $2,199 | 114,019 | Feb 13, 2025 |
| Jan 10, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -12,372 | $7.30 | $90k | 118,674 | Jan 14, 2025 |
| Jan 10, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -1,837 | $8.01 | $15k | 116,837 | Jan 14, 2025 |
| Jan 13, 2025 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock10b5-1 | -2,264 | $6.47 | $15k | 114,573 | Jan 14, 2025 |
| Nov 11, 2024 | SERA SERA PROGNOSTICS, INC. | SOpen-market sale Class A Common Stock | -4,727 | $7.32 | $35k | 131,046 | Nov 12, 2024 |
Questions about Robert Gardner Harrison
Answered from the filings on this page, as of the latest one.
Is Robert Gardner Harrison buying or selling?
In the last 12 months Robert Gardner Harrison reported 0 open-market buys worth $0 and 9 open-market sells worth $56k on SEC Form 4; the latest was sold $1,461 of SERA on Mar 11, 2026. Grants, option exercises and tax withholding are not counted.
How did Robert Gardner Harrison's past buys perform?
Not measured yet. InsiderTell needs three past buys with six months of prices to publish a track record, and Robert Gardner Harrison has 0.
Where does Robert Gardner Harrison file Form 4?
Robert Gardner Harrison has filed Form 4 at SERA (SERA PROGNOSTICS, INC.) as Chief Information Officer. A Form 4 is required of officers, directors and holders of more than 10% of a share class within two business days of a trade.
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.