# Keith Grinstein

> Keith Grinstein is a startup investor at Second Avenue Partners. See 0 investments, check sizes, portfolio. Updated Aug 2026.

- Type: Angel Investor
- Fund: [Second Avenue Partners](https://shizune.co/investors/profile/second-avenue-partners)
- Last updated: Aug 2026

Keith Grinstein is a startup investor at Second Avenue Partners. Sadly, Mr Keith Grinstein passed away in September 2008. Here's a link:http://seattletimes.nwsource.com/html/localnews/2008214675_grinsteinobit30.html*************Mr. Grinstein has more than fifteen years of executive and board experience spanning across the telecommunications, the Internet, and venture capitalindustries. He currently serves as chairman of Coinstar Inc. (NASDAQ: CSTR) and as a member of the board directors and audit committees of F5 Networks (NASDAQ: FFIV), Labor Ready (NYSE: LRW), and Nextera (NASDAQ: NXRA).Mr. Grinstein is a partner of Second Avenue Partners, a venture capital firm which is focused on emerging Internet businesses. He has held a number of senior executive positions, serving previously as Nextel International Inc.'s president and chief executive officer and prior to that president and chief executive officer of the Aviation Communications Division of AT&T Wireless (formerly McCaw Cellular Communications).Mr. Grinstein is an experienced public company audit committee member and has lectured extensively on Sarbanes-Oxley compliance. In 2003, Mr. Grinstein testified in front of the US Senate Banking Committee on behalf of NASDAQ small and mid-cap companies regarding the effects of Sarbanes-Oxley legislation. Mr. Grinstein is also a frequent lecturer on Section 404 of Sarbanes-Oxley, executive compensation and director duties; and has lectured on director duties at the University of Washington Business School and Seattle University Law School.A successful venture capitalist, Mr. Grinstein was a seed-capital investor in Amazon.com (NASDAQ: AMZN). He is a founding partner of Second Avenue Partners, a VC group funding Pacific Northwest early-stage companies. In addition, he has been a driving force behind structuring a number of leading companies including Pathogenesis, VaxGen (VXGN: PK), Tegic, HouseValues (NASDAQ: SOLD), Wireless Services, Nordstrom.com of Nordstrom Inc. (NYSE: JWN), Superconductor Collider Corporation, Neah Power (NPWS: PK), Insitu, and Ice Energy.Mr. Grinstein holds a B.A. in education from Yale University and a J.D. magna cum laude from Georgetown University Law Center.

## About Second Avenue Partners

VC Fund · Seattle, United States

Second Avenue Partners provide management, strategy and capital for early stage companies. The following companies are in their portfolio... -Rubicon Interactive -Sports Technologies Inc. -Ice Energy -Newsvine -Azaleos -You Software -Revenue Science -Insitu Group -Bocada -HouseValues.com -WaveMarket -Terabeam -Essention

5 contacts available at Second Avenue Partners.

| Name | Title | Profile |
| --- | --- | --- |
| Chris O'Connor | President | https://shizune.co/investors/profile/chris-o-connor-f1a2 |
| Keith Grinstein | Associate | https://shizune.co/investors/profile/keith-grinstein |
| Mike Slade | Co-Founder & Partner | https://shizune.co/investors/profile/mike-slade |
| Nick Hanauer | Partner | https://shizune.co/investors/profile/nick-hanauer |
| Pete Higgins | Founding Partner | https://shizune.co/investors/profile/pete-higgins |

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