# Bill Kaiser

> Bill Kaiser is a Series B investor at Greylock backing Software and Enterprise Software. See 7 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [Greylock](https://shizune.co/investors/profile/greylock)
- Location: Menlo Park, United States
- Total investments: 7
- Lead investor: 57%
- Last updated: Aug 2026
- LinkedIn: https://www.linkedin.com/in/billkaiser

Bill Kaiser is a Series B investor at Greylock in Menlo Park focused on Software and Enterprise Software. Bill Kaiser is based out of Boston, Massachusetts and is the Partner of Greylock. Bill previously worked at Red Hat as a Board Member. Bill Kaiser attended the Massachusetts Institute of Technology.

## Investment focus

### Industry

| Industry | Investments | Share |
| --- | --- | --- |
| Software | 2 | 29% |
| Enterprise Software | 2 | 29% |
| Email | 1 | 14% |
| Linux | 1 | 14% |
| Internet | 1 | 14% |

16 industries tracked in total.

### Stage

| Stage | Investments | Share |
| --- | --- | --- |
| Series B | 3 | 43% |
| Series A | 2 | 29% |
| Funding Round | 2 | 29% |

## Investments

| Company | Description | Amount | Stage | Date | Website |
| --- | --- | --- | --- | --- | --- |
| Full Capture Solutions | Full Capture Solutions, Inc. develops predictive, analytic-driven solutions for the insurance industry. Its analytic technology is applied to insurance claims for discovery, forensic analysis, and predictive modeling. Its applications include automobile, environmental, liability, property, workers compensation, and recovery operations. Full CaptureSolutions, was founded in 2004 and is headquartered in East Hartford, Connecticut. | $7M | Series B | Sep 25, 2006 |  |
| Constant Contact | Constant Contact provides email marketing, social media marketing, event marketing, and online survey tools to help small organizations grow their businesses by building stronger customer relationships.More than 500,000 small businesses, nonprofit organizations, and member associations rely on Constant Contact's easy-to-use, affordableonline tools to create and deliver personalized, professional communications that engage customers, members and prospects wherever they congregate online -- from their email inboxes to their social networks. Launched in 1998, Constant Contact made email marketing simple for small organizations and continues this tradition today providing the education and tools to make social media marketing simple for small organizations as well.As an industry leader in permission based online marketing, Constant Contact partners with the leading providers of online marketing and social media marketing solutions. Constant Contact welcomes developers and partners to utilize its API and contribute to its Constant Contact App MarketPlace. | $15M |  | Jun 30, 2006 |  |
| Reflectent Software | Reflectent develops enterprise scalable End-User Systems Management software that complements traditional system and network management applications by providing an integrated, real-time view of enterprise applications from the end-user's perspective. Reflectent reduces the total cost of ownership of connected, mobile, and heterogeneousend-user devices and applications by pinpointing problems between networks, servers, and end-user devices. This results in increased application uptime and availability, automation of labor intensive processes, consolidation of underutilized applications, and the proactive management of mission-critical business applications at the desktop. | $10M | Series B | Jan 16, 2004 |  |
| Reflectent Software | Reflectent develops enterprise scalable End-User Systems Management software that complements traditional system and network management applications by providing an integrated, real-time view of enterprise applications from the end-user's perspective. Reflectent reduces the total cost of ownership of connected, mobile, and heterogeneousend-user devices and applications by pinpointing problems between networks, servers, and end-user devices. This results in increased application uptime and availability, automation of labor intensive processes, consolidation of underutilized applications, and the proactive management of mission-critical business applications at the desktop. | $3.5M | Series A | May 27, 2003 |  |
| NTRU Cryptosystems | NTRU Cryptosystems, Inc. was founded in 1996 by four Brown University mathematicians and cryptographers, and today ranks as one of the most innovative providers of security solutions for the New Internet Economy.Today, NTRU is a fast-growing, well-run, well-funded company delivering security solutions to the wireless data communications andcontent protection markets. Their focus is consumer devices and the server infrastructures that support them ... and on content protection to support digital media delivery mechanisms and protect content owners from piracy. Only NTRU enables new security paradigms and delivers. | $26.1M | Series B | Oct 09, 2001 |  |
| NTRU Cryptosystems | NTRU Cryptosystems, Inc. was founded in 1996 by four Brown University mathematicians and cryptographers, and today ranks as one of the most innovative providers of security solutions for the New Internet Economy.Today, NTRU is a fast-growing, well-run, well-funded company delivering security solutions to the wireless data communications andcontent protection markets. Their focus is consumer devices and the server infrastructures that support them ... and on content protection to support digital media delivery mechanisms and protect content owners from piracy. Only NTRU enables new security paradigms and delivers. | $11M | Series A | Apr 11, 2000 |  |
| Red Hat | Red Hat is a company dedicated to free and open source software, and a major Linux distribution vendor.The company is known for its enterprise operating system Red Hat Enterprise Linux, and more recently through the acquisition of open source enterprise middleware vendor JBoss. Red Hat provides operating system platforms along with middleware,applications, and management solutions, as well as support, training, and consulting services. |  |  | Sep 29, 1998 |  |

7 of 7 investments shown.

## Co-investors
- [Sigma Partners](https://shizune.co/investors/profile/sigma-partners) — VC Fund, 2 deals together
- [Sony](https://shizune.co/investors/profile/sony) — VC Fund, 2 deals together
- [3i Group](https://shizune.co/investors/profile/3i-group) — VC Fund, 1 deal together
- [Benchmark](https://shizune.co/investors/profile/benchmark) — VC Fund, 1 deal together
- [Commonwealth Capital Ventures](https://shizune.co/investors/profile/commonwealth-capital-ventures) — VC Fund, 1 deal together
- [Globespan Capital Partners](https://shizune.co/investors/profile/globespan-capital-partners) — VC Fund, 1 deal together

## About Greylock

VC Fund · Menlo Park, United States

Greylock Partners invests in entrepreneurs that focus on consumer and enterprise software companies. The firm invests in companies that define new markets, including Airbnb, AppDynamics, Apptio, Arista Networks (NYSE: ANET), Cloudera, Docker, Dropbox, Facebook (Nasdaq: FB), LinkedIn (NYSE: LNKD), Medium, Nextdoor, Palo Alto Networks (NYSE: PANW),Pandora (NYSE: P), Pure Storage, and Workday (NYSE: WDAY).It was founded in 1965 and headquartered in Menlo Park, California.

5 contacts available at Greylock.

| Name | Title | Profile |
| --- | --- | --- |
| Bill Kaiser | Partner | https://shizune.co/investors/profile/bill-kaiser |
| David Wadhwani | Venture Partner | https://shizune.co/investors/profile/david-wadhwani |
| Howard Cox | Special Limited Partner | https://shizune.co/investors/profile/howard-cox |
| Jason Risch | Investor | https://shizune.co/investors/profile/jason-risch |
| Mike Duboe | General Partner | https://shizune.co/investors/profile/mike-duboe |

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## FAQ

### What does Bill Kaiser invest in?

Bill Kaiser invests primarily in Software, Enterprise Software and Email startups, most often at Series B and Series A stage. Most of the 7 investments tracked by Shizune back companies in United States. The Investment Focus section breaks down every industry, stage and country in the portfolio.

### 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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