Investors / United States / S28 Capital
S28 Capital
Venture capital · San Francisco, CA, United States · North America
S28 Capital is a venture firm that writes $1M to $5M checks into early-stage companies, typically leading or co-leading Seed rounds and participating in later rounds. It focuses on software and technology B2B businesses, including product-driven applications, developer tools, and infrastructure such as data and security.
Invests inCybersecuritySpace & Defense
In its own wordsb2b softwaredeveloper toolsinfrastructuredatasecurityenterprise
Your fit with S28 Capital
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See how your round matches what it backs, point by point.
Or find every investor that fitsS28 Capital lists 1 checked portfolio company on its own site and is named in 1 funding round. Its most frequent entry is Seed, 100% of the companies with a known first round. Its largest themes are Cybersecurity (50%) and Space & Defense (50%). 100% of its companies are based in United States. It invests most often alongside Andreessen Horowitz, CRV and Georgian.
Counts come from funding rounds that name S28 Capital, complete from mid-2025: earlier rounds appear only when they were reported later. Round amounts and full round histories are on Fundup AI.
Entry stage
share of companies by the stage of its first roundShow as a table
| Value | |
|---|---|
| Pre-seed | 0% |
| Seed | 100% |
| Series A | 0% |
| Series B | 0% |
| Growth | 0% |
Activity by year
rounds it joined, last 10 yearsShow as a table
| Total | Rounds it led | |
|---|---|---|
| '17 | 0 | 0 |
| '18 | 0 | 0 |
| '19 | 0 | 0 |
| '20 | 0 | 0 |
| '21 | 0 | 0 |
| '22 | 1 | 0 |
| '23 | 0 | 0 |
| '24 | 0 | 0 |
| '25 | 0 | 0 |
| '26 | 0 | 0 |
Invests most often with
firms sharing its portfolio companiesShow as a table
| Share | |
|---|---|
| Andreessen Horowitz | 1 |
| CRV | 1 |
| Georgian | 1 |
| Madrona | 1 |
| Preston-Werner Ventures | 1 |
| South Park Commons | 1 |
Its portfolio companies
where they are based, and what their own sites showSite status
- Site answers1100%
- No longer answers00%
- Points to another company00%
- Parked or sold domain00%
A site that stops answering three checks in a row is counted as no longer answering; that is not proof of closure. A site that points to another company is often an acquisition.
Investment themes
share of its checked companiesThis firmAll checked companies
Show as a table
| This firm | All checked companies | |
|---|---|---|
| Cybersecurity | 50% | 4% |
| Space & Defense | 50% | 3% |
Co-investor network
who it backs companies with, and who they back togetherAll co-investors or Compare portfolios with Andreessen Horowitz
Compare S28 Capital head to head
portfolio size, rounds, entry stages, themes and the companies both backThree or more firms at once: portfolio overlap.
Recent portfolio activity
when companies last raised with S28 Capital| Date | Company | Stage |
|---|---|---|
| 30 Nov 2022 | Seed |
Round details for S28 Capital
Amounts, full round histories and every co-investor in S28 Capital's rounds are on Fundup AI. VCinfo covers investors and their portfolios.
Portfolio
1 company checked against their own sites| Company | What it does | Themes | First round with it | Evidence |
|---|---|---|---|---|
| Clerk provides authentication and user management services for modern applications | CybersecuritySpace & Defense | Nov 2022Seed | Funding round |
About this data
site last read 5 Nov 2026- Site
- s28capital.com
- Last read
- 5 Nov 2026
- Watching since
- 5 Nov 2026
- Rounds since
- 30 Nov 2022
- Companies checked
- 1
Rates come from what VCinfo has observed since observation_start. Firms tend to remove companies that closed, so early rates understate reality. A company leaving a portfolio page does not mean it closed or exited. An unreachable site means our checks failed, nothing more.
Get S28 Capital's profile as data
Pull S28 Capital's portfolio, co-investors and changes through one API key or MCP, open every portfolio row, compare it with other firms, and get an email when it adds a company or files a fund.
Work email, sign-in link by email. Already have an account? Log in- Ask AI5 plain-English investor searches a day
- Full listsEvery portfolio row and two-firm overlap
- API and MCP100 REST or MCP calls a month, one key
- AlertsFollow 5 investors for portfolio and fund changes
$ curl -H "X-API-Key: YOUR_KEY" \
https://api.vcinfo.io/v1/firms/s28capital.com
# also
GET /v1/firms/s28capital.com/portfolio
GET /v1/firms/s28capital.com/coinvestors
GET /v1/firms/s28capital.com/news