# Mark Horne

> Mark Horne is a debt financing investor at Plymouth Growth backing Enterprise Software and VoIP. See 14 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [Plymouth Growth](https://shizune.co/investors/profile/plymouth-venture-partners)
- Location: Ann Arbor, United States
- Total investments: 14
- Last investment: Dec 2017
- Lead investor: 64%
- Last updated: Aug 2026

Mark Horne is a debt financing investor at Plymouth Growth in Ann Arbor focused on Enterprise Software and VoIP. Mark joined Plymouth as an investor and advisor in 2005 as an outgrowth of his long term friendship with Ian Bund, Plymouth’s founder. Since that time he and Ian successfully executed a succession plan where Mark took over the role of chief executive office and managing partner in 2007, and he has provided the primary leadership for the firm eversince. He sourced, closed and exited several successful deals in PVP 1, including Guidepoint Systems, American Broadband & Telephone and Pump Engineering. Mark helped define the regional growth stage strategy for PVP 2 and has built a strong team of experienced professionals who know how to collaboratively grow equity value and ultimately harvest that value for strong returns.Mark began his career with Price Waterhouse in Toronto and worked for 20 years as the chief financial officer of several privately-held growth stage businesses, ranging in size from $10 to $150 million. Mark is a former NJ licensed CPA. He holds an M.B.A. from Widener University and a B.B.A in business administration from Cedarville University.

## Investment focus

### Industry

| Industry | Investments | Share |
| --- | --- | --- |
| Enterprise Software | 2 | 14% |
| VoIP | 1 | 7% |
| Lighting | 1 | 7% |
| Security | 1 | 7% |
| Shipping | 1 | 7% |

21 industries tracked in total.

### Stage

| Stage | Investments | Share |
| --- | --- | --- |
| Debt Financing | 4 | 29% |
| Series A | 2 | 14% |
| Series B | 2 | 14% |
| Series D | 2 | 14% |
| Funding Round | 1 | 7% |

## Investments

| Company | Description | Amount | Stage | Date | Website |
| --- | --- | --- | --- | --- | --- |
| Pacejet Logistics | Pacejet is a preferred cloud-based platform for enterprise shipping. With Pacejet, customers grow their businesses with better service, lower costs, continuous delivery improvement. Ship faster with fewer errors and less data entry using integration to leading ERP systems including NetSuite, Microsoft, Infor, SAP, Acumatica, and Plex. Pacejetalso integrates into custom ERPs using their RESTful API. With its headquarters in Columbus, Ohio, offices across the United States, and are a partnership with 3Gtms, Pacejet has a knowledgeable and dedicated team who understand supply chain and logistics, and often come from specific industry verticals like retail or consumer technology. | $3.2M | Series D | Dec 04, 2017 |  |
| Pacejet Logistics | Pacejet is a preferred cloud-based platform for enterprise shipping. With Pacejet, customers grow their businesses with better service, lower costs, continuous delivery improvement. Ship faster with fewer errors and less data entry using integration to leading ERP systems including NetSuite, Microsoft, Infor, SAP, Acumatica, and Plex. Pacejetalso integrates into custom ERPs using their RESTful API. With its headquarters in Columbus, Ohio, offices across the United States, and are a partnership with 3Gtms, Pacejet has a knowledgeable and dedicated team who understand supply chain and logistics, and often come from specific industry verticals like retail or consumer technology. | $3.2M | Series D | Dec 04, 2017 |  |
| XanEdu | XanEdu is helping institutions change the course of learning and instruction with innovative solutions for creating, delivering, and managing course materials. They help educators and learners save money, improve efficiency, collaborate, engage more with content, and improve learning outcomes. XanEducourse materials, including CoursePacks,textbooks and lab manuals, are 100 percent copyright compliant and accessible on iPad and Android tablets. | $8.1M |  | Jul 13, 2015 |  |
| LYNX Network Group | LYNX Network Group was organized in June of 2003 by Gerald Philipp, Gregg Rutgers and Chris Barber each with a varied background in telecommunications dating to the early 1990s. With an advanced understanding of the industry, they quickly climbed to the top of the Ameritech (Midwest RBOC) Distributor program selling a very unique blend of solutionsto a fast growing and still maturing voice communications market. In the mid 1990s they focused on an emerging trend that took them into the data aspect of telecommunications. Individually, they participated in the internet boom by providing data services to the growing ISP market. Over this period of rapid growth they were able to develop key relationships while maintaining a keen sense for emerging trends in telecommunications. These relationships with colleagues and customers and the ability to recognize new directions within the industry brought them together to form LYNX. |  | Series A | Mar 31, 2015 |  |
| Keyfactor | Keyfactor, formerly Certified Security Solutions (CSS), is a leading provider of secure digital identity management solutions that enables organizations to confirm authenticity, and ensure the right things are interacting in the right ways in our connected world.From an enterprise managing millions of devices and applications that affect people’slives every day, to a manufacturer aiming to ensure its product will function safely throughout its life cycle, Keyfactor empowers global enterprises with the freedom to master every digital identity. Its clients are the most innovative brands in the industries where trust and reliability matter most. | $1M | Series B | Mar 09, 2015 |  |
| XanEdu | XanEdu is helping institutions change the course of learning and instruction with innovative solutions for creating, delivering, and managing course materials. They help educators and learners save money, improve efficiency, collaborate, engage more with content, and improve learning outcomes. XanEducourse materials, including CoursePacks,textbooks and lab manuals, are 100 percent copyright compliant and accessible on iPad and Android tablets. | $700K | Debt Financing | May 01, 2014 |  |
| Keyfactor | Keyfactor, formerly Certified Security Solutions (CSS), is a leading provider of secure digital identity management solutions that enables organizations to confirm authenticity, and ensure the right things are interacting in the right ways in our connected world.From an enterprise managing millions of devices and applications that affect people’slives every day, to a manufacturer aiming to ensure its product will function safely throughout its life cycle, Keyfactor empowers global enterprises with the freedom to master every digital identity. Its clients are the most innovative brands in the industries where trust and reliability matter most. | $3.5M | Series A | Mar 24, 2014 |  |
| XanEdu | XanEdu is helping institutions change the course of learning and instruction with innovative solutions for creating, delivering, and managing course materials. They help educators and learners save money, improve efficiency, collaborate, engage more with content, and improve learning outcomes. XanEducourse materials, including CoursePacks,textbooks and lab manuals, are 100 percent copyright compliant and accessible on iPad and Android tablets. | $4M | Series B | Mar 28, 2013 |  |
| LYNX Network Group | LYNX Network Group was organized in June of 2003 by Gerald Philipp, Gregg Rutgers and Chris Barber each with a varied background in telecommunications dating to the early 1990s. With an advanced understanding of the industry, they quickly climbed to the top of the Ameritech (Midwest RBOC) Distributor program selling a very unique blend of solutionsto a fast growing and still maturing voice communications market. In the mid 1990s they focused on an emerging trend that took them into the data aspect of telecommunications. Individually, they participated in the internet boom by providing data services to the growing ISP market. Over this period of rapid growth they were able to develop key relationships while maintaining a keen sense for emerging trends in telecommunications. These relationships with colleagues and customers and the ability to recognize new directions within the industry brought them together to form LYNX. |  | Debt Financing | Feb 01, 2013 |  |
| Relume Technologies | Relume manufactures highly efficient, cost-effective LED lighting products based on its patented Silver Circuitry thermal management technology.Incorporated in 1994 as an LED research and development company, Relume quickly became a leading innovator by recognizing and responding to the critical need for advanced thermal management to accompanythe strides being made in LED technology.Relume has successfully demonstrated how LED technology can be adapted to replace traditional lighting, particularly in safety critical applications. Relume has developed a number of prototype lighting systems related to covert military communications, mobile hospital and command shelters and LED vehicle lighting systems. | $800K | Debt Financing | Oct 01, 2012 |  |

10 of 14 investments shown.

## Co-investors
- [Plymouth Growth](https://shizune.co/investors/profile/plymouth-venture-partners) — VC Fund, 10 deals together
- [Plymouth Growth](https://shizune.co/investors/profile/plymouth-growth) — VC Fund, 4 deals together
- [Beringea](https://shizune.co/investors/profile/beringea) — VC Fund, 1 deal together
- [Western Technology Investment](https://shizune.co/investors/profile/western-technology-investment) — VC Fund, 1 deal together

## About Plymouth Growth

VC Fund · Ann Arbor, United States

Plymouth Growth invests in mid-continent B2B software and technology companies – with $3MM to $10MM in revenue, proven business models, and strong teams – that are ready to scale. The Plymouth team brings decades of experience as operators, advisors, and investors, and understands that while metrics matter, it’s people that are critical to growth.We look beyond the numbers to understand businesses, teams, and cultures, and we seek to partner with entrepreneurs that have accomplished a lot with a little. Based in Ann Arbor, MI and actively investing out of its fifth fund, Plymouth Growth helps teams achieve smart, proven growth. For more information on Plymouth and its investments, please visit www.plymouthgp.com.

5 contacts available at Plymouth Growth.

| Name | Title | Profile |
| --- | --- | --- |
| Alison Todak | Director of Platform | https://shizune.co/investors/profile/alison-today |
| Chris Frick | Chief Financial Officer | https://shizune.co/investors/profile/chris-frick |
| Ian Bund | Co-Founder & Partner | https://shizune.co/investors/profile/ian-bund |
| Mark Horne | Partner | https://shizune.co/investors/profile/mark-horne |
| Alison Todak | Director of Platform | https://shizune.co/investors/profile/alison-todak |

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## FAQ

### What does Mark Horne invest in?

Mark Horne invests primarily in Enterprise Software, VoIP and Lighting startups, most often at Debt Financing and Series A stage. Most of the 14 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 Horne last invest?

The most recent investment recorded for Mark Horne closed in Dec 2017. Shizune tracks 14 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.

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