Mantel
Cambridge, US · Founded 2022 · Delaware corporation · 6 known investors
Mantel Capture, Inc. appears to operate in process engineering and commissioning, with roles referencing boilers, licensing, and research; the page itself provides no explicit statement of the company's product or market.
Founders & leadership
Mantel was founded in 2022 by Cameron Halliday, Danielle Rapson, Danielle Colson, and Sean Robertson.
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Cameron HallidayinCo-founder and CEOHe completed a PhD and an MBA at MIT, where he worked as a graduate research assistant and took consulting placements with Shell and Emirates Global Aluminium through the MIT Practice School, and spent a summer at Boston Consulting Group. He was named an Innovator Fellow at Breakthrough Energy from 2022 to 2024.
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Danielle RapsoninCo-founder · Chief Operating Officer
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Danielle ColsonCofounder30 Under 30 2023
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Sean RobertsoninCo-founder and CTOHe earned his PhD at MIT's Mesoscale Nuclear Materials Group, where he also completed master's research and served as a Communication Lab Fellow in the Department of Nuclear Science and Engineering. Before returning to graduate study, he was a senior design engineer at Transatomic Power, and he is a Breakthrough Energy Fellow.
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Hoosiweng OwNamed on SEC filing
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Dan LeffNamed on SEC filing
Board
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Hooisweng OwBoard director
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Hector MacQuarrieBoard director
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Investors · 6
Eni NextBoston
New Climate VenturesHouston
The Engine VenturesCambridge
Shell VenturesreportedLondon
Waverley CapitalreportedPalo Alto · $500K – $10Mvia Daniel V. Leff · board
Also in the syndicate · 1
Shell
Reported raises · per SEC filings
Form D private placements$50.5M disclosed across 4 rounds · 2022–2026
▶$18.3MraisedAug 2026 · 7 investors · OtherRule 506(b)
▶$18.3MraisedAug 2026 · 7 investors · Other
Rule 506(b)Officers, directors & promoters on the filing
- Cameron HallidayExecutive Officer, Director
- Michael KearneyDirector
- Hector MacQuarrieDirector
- Hoosiweng OwDirector
- Danielle RapsonDirector
- Dan LeffDirector
- Offering amount
- $25M
- Amount sold
- $18.3M
- First sale
- Jul 2026
- Incorporated
- Corporation, Delaware, 2022
- Federal exemptions
- 06b
▶$29.4MraisedSep 2024 · 13 investors · OtherRule 506(b)
▶$29.4MraisedSep 2024 · 13 investors · Other
Rule 506(b)Officers, directors & promoters on the filing
- Hooisweng OwDirector
- Michael KearneyDirector
- Hector MacQuarrieDirector
- Cameron HallidayExecutive Officer, Director
- Daniel LeffDirector
- Danielle RapsonExecutive Officer, Director
- Offering amount
- $30M
- Amount sold
- $29.4M
- First sale
- Jun 2024
- Incorporated
- Corporation, Delaware, 2022
- Federal exemptions
- 06b
▶$700KraisedJan 2024 · 1 investors · Other EnergyRule 506(b)
▶$700KraisedJan 2024 · 1 investors · Other Energy
Rule 506(b)Officers, directors & promoters on the filing
- Michael KearneyDirector
- Danielle ColsonExecutive Officer, Director
- Cameron HallidayExecutive Officer, Director
- Offering amount
- $700K
- Amount sold
- $700K
- First sale
- Dec 2023
- Incorporated
- Corporation, Delaware, 2022
- Federal exemptions
- 06b
▶$2MraisedSep 2022 · 2 investors · OtherRule 506(b)
▶$2MraisedSep 2022 · 2 investors · Other
Rule 506(b)Officers, directors & promoters on the filing
- Cameron HallidayExecutive Officer, Director
- Danielle ColsonDirector
- Sean RobertsonDirector
- Offering amount
- $2M
- Amount sold
- $2M
- First sale
- Aug 2022
- Incorporated
- Corporation, Delaware, 2022
- Federal exemptions
- 06b
Source: SEC EDGAR Form D. Amounts as filed; amended filings shown once at their latest values.
Founder mafia
2 people who came through Mantel went on to found or lead other companies.
Competitors · 2
by search overlap
Greentownlabs6 shared keywordsGreentown Labs is a climatetech startup incubator that supports and houses early-stage entrepreneurs, connecting them with corporate partners, investors, and community resources to develop and commercialize energy and climate technologies. It operates locations in Boston and Houston in the United States.
Privco4 shared keywordsPrivCo provides a financial intelligence platform covering 5M+ U.S. private companies with proprietary revenue, EBITDA, and valuation estimates, plus AI-powered search and an API. It serves investment banking, private equity, venture capital, sales, and corporate M&A teams to source deals, build acquisition lists, and conduct due diligence.
Companies competing with Mantel for the same Google search keywords, organic and paid, via search-intersection analysis.
Non-dilutive funding · 1 SBIR/STTR award
Federal grants — no equity taken| Agency | Phase | Year | Amount |
|---|---|---|---|
| U.S. ArmyArmy | Phase I | 2023 | $245.9K |
Source: SBIR.gov award data (U.S. Small Business Administration). SBIR/STTR awards are competitive federal R&D grants and contracts — non-dilutive capital alongside any venture rounds above.
In the news
Frequently asked questions
- What does Mantel do?
- Mantel Capture, Inc. appears to operate in process engineering and commissioning, with roles referencing boilers, licensing, and research; the page itself provides no explicit statement of the company's product or market.
- Who founded Mantel?
- Mantel was founded by Cameron Halliday, Danielle Rapson, Danielle Colson, Sean Robertson in 2022.
- Who are Mantel's investors?
- Mantel's investors include Eni Next, New Climate Ventures, The Engine Ventures, Shell Ventures, Waverley Capital.
- How much funding has Mantel raised?
- Mantel has disclosed $50.5M raised across 4 rounds.
- Where is Mantel headquartered?
- Mantel is headquartered in Cambridge, US.