Mainspring Funding
QuietWest Palm Beach, FLEnergy, Manufacturing, RetailingLast fund filed July 2026
2 on a current fund
last 24 months
across filed funds
| Vehicle | Filed | Target | Sold to date | Investors |
|---|---|---|---|---|
| Mainspring Funding II | July 2026 | $20M | $2.9M | 13 |
| MAINSPRING FUNDING | February 2023 | $711,974 | $6.8M | 34 |
Amounts are Item 13 as filed: the target is the whole offering, and the amount sold is cumulative across amendments rather than a final close. The filing carries no per-investor amount, so a firm’s own cheque is not recoverable here.
2 partners are named across this firm’s filings, 2 of them on a fund it is deploying now.
| Partner | Activity | Categories | Board seats | Last 24mo |
|---|---|---|---|---|
| Alexander Weiss | Quiet | Climate & energy, Cybersecurity, Fintech | 11 | 0 |
| James Huff | Quiet | Climate & energy, Manufacturing & industrials, Cybersecurity | 8 | 0 |
Activity is filed board seats in the last 24 months: 4+ Active, 2–3 Selective, 1 Slowing, none Quiet. A firm's tier totals its partners, so an active firm may be four partners with one seat each. It undercounts partners who invest without taking a board seat, and filings lag a closing by weeks, so Quiet means the paperwork is quiet, not the person.
Classified sectors of Mainspring Funding’s own portfolio companies, based on 16 with a verified or cited source.
Not a filing value: this is Lev’s own classification of each company, one company one vote regardless of how many of Mainspring Funding’s partners are named on its board, shown only when we found a specific, checkable source. Companies with no source read as unclassified and are left out of the shares above.
| Firm | Shared boards | Companies |
|---|---|---|
| Clearsky Security | 19 | Aquicore, Co3 Systems, Cyber Global Risk Exchange, CYLANCE, Entic, EtaGen, Fermata, GOLD HOLDINGS, Greensmith Energy Management Systems, MATTRESS FIRM HOLDING, NEXTracker, NOVINIUM, PrecisionHawk, Space Time Insight, Spruce Finance, T-Rex Group, Ubicquia, UNIVERSAL SECURITY INSTRUMENTS, Verengo |
| Clearsky Power Technology | 18 | Aquicore, Co3 Systems, CYLANCE, Entic, EtaGen, Fermata, GOLD HOLDINGS, Greensmith Energy Management Systems, MATTRESS FIRM HOLDING, NEXTracker, NOVINIUM, PrecisionHawk, Space Time Insight, Spruce Finance, T-Rex Group, Ubicquia, UNIVERSAL SECURITY INSTRUMENTS, Verengo |
| SJF Ventures | 2 | NEXTracker, NOVINIUM |
| DBL Partners Tiab | 1 | NEXTracker |
| DFJ Growth | 1 | CYLANCE |
| Glasswing Ventures | 1 | Co3 Systems |
| Khosla Ventures | 1 | EtaGen |
| NEW York Life Insurance | 1 | Ubicquia |
| Rise | 1 | MATTRESS FIRM HOLDING |
| SYN Ventures | 1 | CYLANCE |
| TPG Healthcare Partners | 1 | MATTRESS FIRM HOLDING |
| TPG Personnel | 1 | MATTRESS FIRM HOLDING |
A shared board seat: a company where filings name a Mainspring Funding partner and a partner at the other firm, both with a clean identity match. Not a claim either firm led or co-led the round, only that both are named on the same board.