Funding profile · Surgical devices

Allotrope Medical

One angel-led round, two Form D filings six weeks apart, and $1.18 million of NSF money that arrived before any of it. The company was acquired in April 2023 and the terms were never disclosed.

$5.05MSold under Regulation D at the last filing, Apr 27, 2021
$4.0MSeries A as announced five weeks later, Jun 1, 2021
$1.18MNSF SBIR obligated, 2018 to 2020, before the first equity sale
90Investors in the amended offering, about $56,000 each

Data as of September 22, 2026. Company-reported figures are labeled.

Rounds at a glance

When Round Amount Investors Source
2018 NSF SBIR Phase I, award 1746570 $224,832 National Science Foundation NSF
2019 to 2020 NSF SBIR Phase II and IIB, award 1852999 $951,914 National Science Foundation NSF
Mar 2021 Equity offering, first sale Mar 1, 2021 $4,532,825 offered; $3,040,313 sold 53 Form D
Apr 2021 Same offering, amended $5,567,034 offered; $5,045,284 sold 90 Form D/A
Jun 2021 Series A, announced $4,000,000 Led by Rockies Venture Club, with nine named angel networks and small funds, among them Tech Coast Angels and Texas Halo Fund Company release
Apr 2023 Acquisition by Northgate Technologies Inc. Not disclosed Northgate Technologies, an affiliate of the Trudell Medical Limited group Acquirer release

What the filings show

Allotrope Medical Inc. · Form D · filed Mar 11, 2021

First sale
Mar 1, 2021
Offered
$4,532,825 equity
Sold
$3,040,313 · $1,492,512 remaining
Investors
53 · average about $57,364
Exemption
Rule 506(b)
Issuer
Delaware corporation, incorporated 2016, Houston, TX
Related persons
Albert Huang (executive officer, director); Donald Gonzales, Mira Sahney and David Franklin (directors)
Filing
SEC EDGAR, CIK 0001702408

Allotrope Medical Inc. · Form D/A · filed Apr 27, 2021

First sale
Mar 1, 2021, unchanged
Offered
$5,567,034 equity, raised by $1,034,209
Sold
$5,045,284 · $521,750 remaining
Investors
90 · average about $56,059
Exemption
Rule 506(b)
Sales compensation
None reported; finders fees $0
Related persons
Identical to the March filing
Filing
SEC EDGAR, CIK 0001702408

Reading the filings

  1. The announcement is smaller than the filing.The June 1, 2021 release calls it “an oversubscribed $4 million Series A financing.” The amended Form D filed five weeks earlier reports $5,045,284 already sold from 90 investors. Either the $4 million refers to a priced tranche inside a larger offering, or the release rounds down by more than a million dollars. No later amendment was filed to settle it.
  2. The checks are angel sized, and the investor list says why.$5,045,284 divided by 90 investors is about $56,059 each. That is consistent with the named participants: nine angel networks and small funds around a lead that is itself an angel group, Rockies Venture Club, rather than an institutional venture syndicate.
  3. The round filled fast at the end.In the 47 days between the two filings, investors went from 53 to 90 and dollars sold from $3,040,313 to $5,045,284. The company also lifted the offering cap by $1,034,209, which issuers do when demand runs past the ceiling, not when they are scraping.
  4. Non-dilutive money came first and did the engineering.NSF obligated $224,832 in Phase I and $951,914 in Phase II and IIB, $1,176,746 in total, all of it before the first equity sale on March 1, 2021. Note that SBIR.gov reports a total of $926,746 for the company because its Phase II line carries only the FY2019 obligation of $701,914 and omits the $250,000 added in FY2020. The NSF award record carries both.
  5. The board never changed.Both filings list the same four related persons, and no seat was added as 37 new investors came in. That is normal for an angel round and unusual for an institutional one.
  6. Nothing was filed after April 2021.No further Form D appears under CIK 0001702408, and the company was acquired 24 months later. Reaching a strategic exit on one angel round is a short capital history by device standards.

Commercial signals

Signal Detail Source type
Regulatory One clearance, 510(k) K200886, Nov 10, 2020. Safer Technologies Program designation announced Nov 2022 with a proposed additional indication. No second clearance has appeared as of Sep 2026. Public record
Manufacturing The FDA listing for the signal box, activation card and four adapters now sits under Northgate Technologies of Elgin, Illinois, created Jan 27, 2025. A separate StimSite listing under Prospect Life Sciences of Westminster, Colorado dates to Mar 18, 2021. Public record
Channel Three-year MAGNET GROUP GPO agreement, contract 4430, Sep 15, 2024 to Sep 14, 2027, alongside the acquirer’s insufflation and smoke removal lines. The group reports roughly 9,000 member facilities. Partner-stated
Revenue model Procedure credits rather than capital sale: a disposable Activation Card that permits a set number of cases before replacement, named as a component in the FDA file. Public record
Clinical evidence No registered trials. One single-patient case report, funded by the company. No MAUDE adverse event reports. Thin
Marketing versus label The GPO listing says the device can “drastically reduce the risk of ureter injury and expedite cystoscopy procedures.” The cleared indication covers only locating and identifying ureters by testing excitability. Differs from the clearance

What to watch

  • A new 510(k) for the cystoscopy indication the 2022 announcement described. None has been filed in four years.
  • Whether the acquirer funds a controlled study behind the injury reduction language in its own sales material.
  • Renewal of the MAGNET GROUP agreement in September 2027, the first public checkpoint on hospital demand.
  • The continuation patent filed September 19, 2025, which indicates the platform is still being prosecuted under new ownership.

The Allotrope Medical story on Healthcare DiscoveryHealthcare Discovery

Related companies

  • VenoStent: Shared investor: Texas Halo Fund. A bioabsorbable polymer sleeve that a surgeon slips over a newly built dialysis fistula and leaves behind to dissolve
  • CellChorus: Shared investor: Texas Halo Fund. A University of Houston spinout that films immune cells one at a time and scores how well each one kills
  • Revolve Surgical: Also in Medical Devices. A Toronto company building a laparoscopic robot that clamps to the operating table instead of filling the room
  • Corveus Medical: Also in Medical Devices. A Houston company building a catheter that deactivates one sympathetic nerve to relieve congestion in heart failure

Sources

  1. Public recordForm D, Allotrope Medical Inc., CIK 0001702408SEC · Mar 11, 2021
  2. Public recordForm D/A, Allotrope Medical Inc., CIK 0001702408SEC · Apr 27, 2021
  3. Public recordNSF awards 1746570 and 1852999, obligation records and project outcomes reportsNational Science Foundation
  4. Public recordSBIR.gov company portfolio, Allotrope Medical Inc.SBIR.gov
  5. Public recordFDA 510(k) K200886 clearance letter and summary, plus device registration and listing recordsFDA · 2020 to 2025
  6. Public recordUS 12,440,265 B2 and related applicationsUSPTO via Google Patents · 2025
  7. IndependentAllotrope Medical Raises $4M in Series A FinancingFinSMEs · Jun 1, 2021
  8. IndependentHouston health tech startup acquired by medical device companyInnovationMap, Natalie Harms · Apr 26, 2023
  9. CompanySeries A financing releasePR Newswire · Jun 1, 2021
  10. AcquirerNorthgate Technologies Inc. Announces Acquisition of Allotrope Medical Inc.Trudell Medical Group · Apr 4, 2023
  11. DistributorNorthgate Technologies contract 4430 listing and award announcementMAGNET GROUP GPO and Surgical Robotics Technology · Sep 2024

Compiled from SEC, NSF, SBIR.gov, USPTO and FDA public records and published reports as of September 22, 2026. Form D notices report offerings under Regulation D; amounts reflect the filing date and may not capture later sales. Healthcare Venture Capital Fund holds no position in Allotrope Medical or Northgate Technologies. This page is not an offer to sell or a recommendation to buy any security.