TNDMTandem Diabetes Care, Inc.Healthcare · Medical - Devicesas of 2026-09-16
Horizon

Issued 2026-09-16 at $17.53 · now $17.53 (2026-09-16, +0.0% since)

Based on its own history, a month from the 2026-09-16 close, TNDM has typically landed between $12.46 and $23.37 — a range of −28.9% to +33.3% from the issuance price $17.53.

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

3,206 overlapping 1 month windows · 2013-11-14 – 2026-08-17 · basis climatology · forecast (batch). Probability up 53.9% (90% CI 51.7–56.1%, ≈1,408 obs).

The cone is anchored at the 2026-09-16 issuance close ($17.53) — 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 TNDM has typically landed a month from the 2026-09-16 close of $17.53 — the range is history, not a prediction.

$12.46worst · -28.9%$23.37best · +33.3%
  • now $17.53 (+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). $17.11 (-2.4%)
  • middle 50%The central range of outcomes — half of similar past periods landed inside it, a quarter finished above, a quarter below. $14.84–$19.39
  • 90% rangeA nine-in-ten range — in about nine of every ten similar past periods the outcome stayed within these bounds. $12.46–$23.37
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 3,206 windows spanning 2013-11-14 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
2016-10-10−76.7%−76.7%+0.0%
2016-10-11−76.0%−76.0%+0.1%
2016-10-07−75.5%−75.5%+0.0%
3 best
2017-08-01+112.6%+0.0%+159.0%
2018-03-21+101.1%+0.0%+106.8%
2018-05-11+98.9%+0.0%+98.9%

3,206 overlapping windows · 2013-11-14 – 2026-09-16 · not cherry-picked

Seasonality · by month iHow this security has tended to do in each calendar month historically — a frequency, never a prediction.

iFor each calendar month, the share of years this security closed higher than the month before, and the average month-over-month return, over ~13 years of its own price history. Cells are shaded by average return. This is historical frequency, not a prediction — no month is a signal.
Jan
46%
−1.6%
n=13
Feb
46%
+3.8%
n=13
Mar
38%
−1.2%
n=13
Apr
54%
+3.5%
n=13
May
38%
−0.0%
n=13
Jun
46%
+2.4%
n=13
Jul
54%
+3.1%
n=13
Aug
69%
+10.5%
n=13
Sep
31%
−7.5%
n=13
Oct
50%
−6.0%
n=12
Nov
42%
−1.6%
n=12
Dec
69%
+6.3%
n=13

Up-frequency and average month-over-month return · historical frequency, not a prediction

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$112026-03-17: 1 insider sale, $4K — Novara Mark David2026-03-05: 1 insider sale, $46 — Novara Mark David2025-08: 2 open-market purchases, $252K2026-03: 2 open-market sales, $4K↑ buys↓ salesofficer Novara Mark David — Sale on 2026-03-17, filed 1 day after the tradeofficer Novara Mark David — Sale on 2026-03-05, filed 4 days after the trade
DatePersonRoleActionShares @ priceValueOwnership Δvs S&P 1mvs S&P 6mOwned afterFiling
2026-03-17Novara Mark DavidofficerSale187 @ $23.05$4K−0.5% of holding−20.9%−39.7%37,656Form 4 · filed 1 day after the trade
2026-03-05Novara Mark DavidofficerSale2 @ $22.81$46−0.0% of holding−12.3%−23.8%35,969Form 4 · filed 4 days after the trade

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.

298 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
2026-08-15Sheridan John FdirectorWithheld for tax5,055160,260Form 4
2026-08-15Sheridan John FdirectorWithheld for tax3,044155,381Form 4
2026-08-15Gasser Elizabeth AnneofficerWithheld for tax1,0291,396Form 4
2026-08-15Hansen Shannon MarieofficerWithheld for tax97631,650Form 4
2026-08-15Vosseller LeighofficerWithheld for tax94252,040Form 4
2026-08-15Carpenter RickofficerWithheld for tax82032,148Form 4
2026-08-15Gasser Elizabeth AnneofficerWithheld for tax589508Form 4
2026-08-15Hansen Shannon MarieofficerWithheld for tax55930,709Form 4
2026-08-15Vosseller LeighofficerWithheld for tax53750,358Form 4
2026-08-15Kyrillos Jean-ClaudeofficerWithheld for tax53530,290Form 4
2026-08-15Morrison SusanofficerWithheld for tax49552,788Form 4
2026-08-15Carpenter RickofficerWithheld for tax45731,358Form 4
2026-08-15Morrison SusanofficerWithheld for tax31451,553Form 4
2026-08-15Hansen Shannon MarieofficerOption exercise1,0973,290Form 4
2026-08-15Vosseller LeighofficerOption exercise2,62418,368Form 4
2026-08-15Vosseller LeighofficerOption exercise1,4964,486Form 4
2026-08-15Vosseller LeighofficerOption exercise2,62452,982Form 4
2026-08-15Vosseller LeighofficerOption exercise1,49650,895Form 4
2026-08-15Sheridan John FdirectorOption exercise9,93469,537Form 4
2026-08-15Sheridan John FdirectorOption exercise5,98217,947Form 4
2026-08-15Sheridan John FdirectorOption exercise9,934165,315Form 4
2026-08-15Sheridan John FdirectorOption exercise5,982158,425Form 4
2026-08-15Morrison SusanofficerOption exercise1,73012,115Form 4
2026-08-15Carpenter RickofficerOption exercise89731,815Form 4
2026-08-15Carpenter RickofficerOption exercise1,61032,968Form 4
2026-08-15Carpenter RickofficerOption exercise8972,692Form 4
2026-08-15Carpenter RickofficerOption exercise1,61011,268Form 4
2026-08-15Gasser Elizabeth AnneofficerOption exercise1,0971,097Form 4
2026-08-15Gasser Elizabeth AnneofficerOption exercise1,9172,425Form 4
2026-08-15Gasser Elizabeth AnneofficerOption exercise1,0973,290Form 4
2026-08-15Gasser Elizabeth AnneofficerOption exercise1,91713,418Form 4
2026-08-15Hansen Shannon MarieofficerOption exercise1,09731,268Form 4
2026-08-15Hansen Shannon MarieofficerOption exercise1,91732,626Form 4
2026-08-15Morrison SusanofficerOption exercise1,0973,290Form 4
2026-08-15Hansen Shannon MarieofficerOption exercise1,91713,418Form 4
2026-08-15Kyrillos Jean-ClaudeofficerOption exercise1,01030,825Form 4
2026-08-15Kyrillos Jean-ClaudeofficerOption exercise1,0107,067Form 4
2026-08-15Morrison SusanofficerOption exercise1,09751,867Form 4
2026-08-15Morrison SusanofficerOption exercise1,73053,283Form 4
2026-07-15Kyrillos Jean-ClaudeofficerWithheld for tax1,92629,815Form 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.