SPTXSeaport Therapeutics, Inc. Common StockHealthcare · Biotechnologyas of 2026-09-16
Horizon

Issued 2026-09-16 at $22.14 · now $22.14 (2026-09-16, +0.0% since)

Based on its own history, a month from the 2026-09-16 close, SPTX has typically landed between $19.72 and $29.15 — a range of −10.9% to +31.6% from the issuance price $22.14.

Range of outcomes in historically similar periods — not a price prediction. Ranges are scored publicly on /methodology.
  • Actual close
  • Typical path (median)
  • Middle 50% of outcomes
  • 90% range

74 overlapping 1 month windows · 2026-05-01 – 2026-08-17 · basis climatology · forecast (batch).

The cone is anchored at the 2026-09-16 issuance close ($22.14) — the price the forecast resolves against on 2026-10-15, not the latest close. The drawn path shape is illustrative (bands widen with √t); every labeled number is real — the anchor, the scored batch p90/IQR endpoints, and the typical move.

Where SPTX has typically landed a month from the 2026-09-16 close of $22.14 — the range is history, not a prediction.

$19.72worst · -10.9%$29.15best · +31.6%
  • now $22.14 (+0.0%)
  • typicalThe typical outcome — half of similar past periods did better and half did worse (not an average, so a few wild periods don't skew it). $24.87 (+12.3%)
  • middle 50%The central range of outcomes — half of similar past periods landed inside it, a quarter finished above, a quarter below. $23.73–$26.02
  • 90% rangeA nine-in-ten range — in about nine of every ten similar past periods the outcome stayed within these bounds. $19.72–$29.15
Actual 1-month windows behind the coneiEvery overlapping 1-month window in this security's own price history was ranked by realized return; shown are the 3 worst and 3 best of 74 windows spanning 2026-05-01 to 2026-09-16. Not cherry-picked — these are the extremes of the full sample. Max drop / max rise are the deepest and highest points reached within each window. See /methodology.
StartReturnMax dropMax rise
3 worst
2026-05-01−13.3%−23.1%+0.0%
2026-06-29−12.3%−19.0%+0.0%
2026-08-17−9.3%−10.9%+14.1%
3 best
2026-07-28+39.9%−0.8%+39.9%
2026-07-29+33.0%+0.0%+41.0%
2026-06-05+29.3%−1.5%+37.0%

74 overlapping windows · 2026-05-01 – 2026-09-16 · not cherry-picked

Reported insider & political trades

Every Form 4 the people closest to this company have filed with the SEC — plotted against the share price, aggregated by month, and shown with the gap between when each trade happened and when it was disclosed. A public record, not advice.

Share price & reported tradesMonthly open-market valueReporting lag — trade date to filing date2026-092026-082026-072026-062026-052026-042026-032026-022026-012025-122025-112025-102025-092025-08$28$152026-06-22: 1 insider purchase, $236K — HOMBACH ROBERT J.2026-05-04: 1 insider purchase, $19.8M — ARCH Venture Partners XII, LLC2026-05: 1 open-market purchase, $19.8M2026-06: 1 open-market purchase, $236K↑ buys↓ salesdirector HOMBACH ROBERT J. — Purchase on 2026-06-22, filed 2 days after the tradedirector ARCH Venture Partners XII, LLC — Purchase on 2026-05-04, filed same day
DatePersonRoleActionShares @ priceValueOwnership Δvs S&P 1mvs S&P 6mOwned afterFiling
2026-06-22HOMBACH ROBERT J.directorPurchase13,000 @ $18.14$236Kownership Δ n/a+18.0%not yet — horizon still open13,000Form 4 · filed 2 days after the trade
2026-05-04ARCH Venture Partners XII, LLCdirectorPurchase1,100,000 @ $18.00$19.8M+21.2% of holding−3.7%not yet — horizon still open6,294,951Form 4 · filed same day

The vs-S&P columns are a labeled look-back on what the stock did after each filing, measured against the index over the same window. Descriptive history, not a claim about the person or a reason to trade.

67 award / exercise / gift records — not counted as purchases

Awards, option exercises, gifts and tax-withholding disposals are shown separately and never counted as open-market purchases or sales — they carry no conviction information.

DatePersonRoleActionSharesOwned afterFiling
2026-05-04Gladstein LanaofficerConversion105,2630Form 4
2026-05-04Chen Michael CunyuanofficerConversion10,5260Form 4
2026-05-04PAUL STEVEN MdirectorConversion210,5260Form 4
2026-05-04Loebel AntonyofficerConversion63,1570Form 4
2026-05-04PureTech Health plctenPercentOwnerConversion40,000,0000Form 4
2026-05-04HEALY JAMESdirectorConversion2,526,3150Form 4
2026-05-04HEALY JAMESdirectorConversion6,052,6310Form 4
2026-05-04Torres DenicedirectorConversion42,1050Form 4
2026-05-04PureTech Health plctenPercentOwnerConversion3,031,5780Form 4
2026-05-04White LaurenofficerConversion21,0520Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2650Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6860Form 4
2026-05-04PureTech Health plctenPercentOwnerConversion8,421,0520Form 4
2026-05-04Gladstein LanaofficerConversion33,51533,515Form 4
2026-05-04White LaurenofficerConversion6,7026,702Form 4
2026-05-04Torres DenicedirectorConversion13,40613,406Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04PAUL STEVEN MdirectorConversion67,031863,031Form 4
2026-05-04Loebel AntonyofficerConversion20,10920,109Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04Chen Michael CunyuanofficerConversion3,3513,351Form 4
2026-05-04HEALY JAMESdirectorConversion1,927,1591,927,159Form 4
2026-05-04HEALY JAMESdirectorConversion804,3792,731,538Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,513,6862,513,686Form 4
2026-05-04ARCH Venture Partners XII, LLCdirectorConversion2,681,2655,194,951Form 4
2026-05-04PAUL STEVEN MdirectorConversion67,031863,031Form 4
2026-05-04Loebel AntonyofficerConversion20,10920,109Form 4
2026-05-04Chen Michael CunyuanofficerConversion3,3513,351Form 4
2026-05-04Gladstein LanaofficerConversion33,51533,515Form 4
2026-05-04Torres DenicedirectorConversion13,40613,406Form 4

Source: SEC Form 4 filings. Each row links to its original filing.

Across 2012–2021, stocks where a CEO, C-suite officer, or director had recently made an open-market common-stock purchase ran about +28 bp per month above the universe average (n=34,268 stock-weeks). A historical tendency, not a prediction.

Congressional disclosures

No congressional trades disclosed for this company.

Research tool, not investment advice — historical frequencies, not recommendations. A product of Marovel Technologies LLC. Full terms.