# Mark Heising

> Mark Heising is a Series A investor at Medley Partners backing Electronics and Energy. See 8 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [Medley Partners](https://shizune.co/investors/profile/medley-partners)
- Total investments: 8
- Last investment: Jun 2024
- Lead investor: 13%
- Last updated: Aug 2026

Mark Heising is a Managing Director of Medley Partners in San Francisco, CA. He founded the firm in 2004.Previously he was the President of VLSI Cores, which designs and licenses cryptographic integrated circuits.He holds six U.S. Patents in cryptography, compression and data communications.Mark serves as a director for Lam Aviation,Sion Power, Solexant and Tabula. On the non-profit side, Mark currently serves on the Board of Directors of the Bipartisan Policy Center and the Environmental Defense Fund.Mark earned a BS in Physics and a MS in Electrical Engineering and Computer Sciences from the University of California at Berkeley.

## Investment focus

### Industry

| Industry | Investments | Share |
| --- | --- | --- |
| Electronics | 2 | 25% |
| Energy | 1 | 13% |
| Chemical | 1 | 13% |
| Consumer | 1 | 13% |
| CleanTech | 1 | 13% |

9 industries tracked in total.

### Stage

| Stage | Investments | Share |
| --- | --- | --- |
| Series A | 2 | 25% |
| Series B | 1 | 13% |
| Series C | 1 | 13% |
| Series D | 1 | 13% |
| Series E | 1 | 13% |

6 stages tracked in total.

## Investments

| Company | Description | Amount | Stage | Date | Website |
| --- | --- | --- | --- | --- | --- |
| Molten Industries | Molten Industries develops clean technology with the goal of decarbonizing the hydrogen market. The company's technology generates the most affordable and environmentally friendly hydrogen. | $25M | Series A | Jun 20, 2024 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $25M | Series E | May 23, 2017 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $10M | Series D | Jan 29, 2015 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $23M | Series C | Jul 01, 2011 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $41.5M | Series C | Jun 04, 2010 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $18.2M | Series B | Oct 29, 2008 |  |
| EnLink Geoenergy Services | EnLink continues to be an innovative leader in the geothermal heat pump (GHP) industry by virtue of its continuous improvement in the installation of underground loop systems, called Earth Heat Exchangers (EHXs).After 14 years in the business, and with 13 US and international patents to its credit, EnLink has a record of reliability and successin EHX installation that is unsurpassed in the industry. EnLink is committed to total professionalism with its clients, its partners and all the stakeholders who participate in their projects. | $30M |  | May 19, 2008 |  |
| Siva Power | Siva Power develops third-generation thin-film PV technologies which increase solar cell efficiency and reduce manufacturing costs, therefore enabling the commercialization of solar modules that generate electricity at competitive rates without depending on government subsidies. Siva Power was founded in 2006 and headquartered in San Jose,California. | $4.3M | Series A | Aug 30, 2007 |  |

8 of 8 investments shown.

## Co-investors
- [Trident Capital](https://shizune.co/investors/profile/trident-capital) — VC Fund, 5 deals together
- [Firelake Capital Management](https://shizune.co/investors/profile/firelake-capital-management) — VC Fund, 4 deals together
- [DBL Partners](https://shizune.co/investors/profile/dbl-investors) — VC Fund, 3 deals together
- [Birchmere Ventures](https://shizune.co/investors/profile/birchmere-ventures) — VC Fund, 2 deals together
- [Olympus Capital Holdings Asia](https://shizune.co/investors/profile/olympus-capital-holdings-asia) — VC Fund, 2 deals together
- [XSeed Capital](https://shizune.co/investors/profile/xseed-capital) — VC Fund, 2 deals together

## About Medley Partners

VC Fund · San Francisco, United States

Medley Partners manages private equity investments on behalf of Jim Simons' family and a number of affiliated entities.Founded in 2004, Medley invests primarily in private equity funds, including buyout, growth equity, venture capital, real estate and distressed in the United States, Europe and Asia, and also participates in co-investmentopportunities with the funds where it is invested.The firm employs a diverse investment approach by geography and industry, actively seeking new investments with strong managers and compelling long-term value fundamentals.

4 contacts available at Medley Partners.

| Name | Title | Profile |
| --- | --- | --- |
| Mark Heising | Founder & Managing Director | https://shizune.co/investors/profile/mark-w-heising |
| Brent Whisenant | Managing Director | https://shizune.co/investors/profile/brent-whisenant |
| Brian S. Schneider | Managing Director | https://shizune.co/investors/profile/brian-s-schneider |
| Edson Maduwura | Controller | https://shizune.co/investors/profile/edson-maduwura |

## Similar investors

### Similar industry
- [Antler](https://shizune.co/investors/profile/antler-be9c) — VC Fund
- [SOSV](https://shizune.co/investors/profile/sosv) — VC Fund
- [Breakthrough Energy Ventures](https://shizune.co/investors/profile/breakthrough-energy-ventures) — VC Fund

### Similar stage
- [Antler](https://shizune.co/investors/profile/antler-be9c) — VC Fund
- [Alumni Ventures](https://shizune.co/investors/profile/alumni-ventures-group) — VC Fund
- [General Catalyst](https://shizune.co/investors/profile/general-catalyst-partners) — VC Fund

### Similar country
- [Alumni Ventures](https://shizune.co/investors/profile/alumni-ventures-group) — VC Fund
- [Right Side Capital Management](https://shizune.co/investors/profile/right-side-capital-management) — VC Fund
- [General Catalyst](https://shizune.co/investors/profile/general-catalyst-partners) — VC Fund

## Featured in investor lists
- [CleanTech Angel Investors in United States](https://shizune.co/investors/cleantech-angel-investors-united-states)

## FAQ

### What does Mark Heising invest in?

Mark Heising invests primarily in Electronics, Energy and Chemical startups, most often at Series A and Series B stage. Most of the 8 investments tracked by Shizune back companies in United States. The Investment Focus section breaks down every industry, stage and country in the portfolio.

### When did Mark Heising last invest?

The most recent investment recorded for Mark Heising closed in Jun 2024. Shizune tracks 8 investments in total for this profile, including round sizes, stages and portfolio companies, all sourced from confirmed public funding rounds and refreshed monthly.

### Is Shizune's investor data accurate?

Yes — every stat on this profile is calculated from confirmed public funding rounds monitored across hundreds of sources since 2020. This profile was last refreshed in Aug 2026 and is updated monthly. Spotted something off? Use the “Suggest an edit” link near the top of the page.

# About Shizune
Shizune.co is an investor database. Core features:
- 48,091 startup investors (angels, VCs, accelerators, and others)
- Email, phone, LinkedIn (for intros), socials, and other contact data
- Updated daily from public funding news
- CSV and Excel export

The User can access the full database FOR FREE after signing up: shizune.co