AI Is Changing Everything. We’re Making Sure It’s Safe.

Rick Caccia has a long history of bringing successful security and compliance products to market, and has held product and marketing leadership roles at Palo Alto Networks, Google, and Symantec. He ran product marketing at ArcSight through its IPO and operations as a public company, and was the first CMO at Exabeam. He has multiple degrees from University of California, Berkeley.

Gil Spencer has led technology teams and security pioneers, founding IronKey (acquired by Imation) and Marble Security (acquired by Proofpoint). He served as a technology leader at AT&T Cybersecurity following AlienVault’s acquisition and founded Spree3D, where he innovated with AI and 3D for video-based brand engagement. Earlier in his career, he was an engineer at Apple in System Software and Quicktime, after which he developed the first Mac DVD player at E4.

Stephanie Gilliam brings significant experience in leading innovative marketing teams focused on developing effective strategies for customer acquisition and retention. Her expertise spans, brand strategy, growth marketing, and customer engagement, enabling her to connect effectively with target audiences. Prior to joining WitnessAI, Stephanie held leadership roles at Imperva and Exabeam, where her sales-focused, data-driven approach fueled company growth and enhanced overall marketing performance. She holds degrees from California Polytechnic State University and The University of Texas.

Faisal Rahman is an accomplished sales leader with over two decades of experience in the cybersecurity industry. He has a proven track record in driving sales growth and leading teams. Faisal’s extensive experience includes nearly a decade at Exabeam as Regional Sales Director and eight years at Imperva as Senior Director of Sales Engineering for the Americas. He began his career as a security engineer at E*TRADE and has a strong educational background with an MBA from Georgia Southern University and a BBA in Management Information Systems from the University of Georgia.

Mark Sierra brings extensive experience in driving financial strategy and operational excellence to WitnessAI. Since 1996, he has worked with VC-backed startups, including those funded by Kleiner Perkins, Sequoia Capital, a16z, Menlo Ventures, and Greylock. Throughout his career, Mark has helped companies raise approximately $1 billion in equity and debt, and he has led or participated in multiple exits, with several former client companies still actively engaged in the market.

Trevor Welsh is a seasoned executive in the AI and cybersecurity sectors. With over two decades of experience in product leadership and innovation, Trevor has been instrumental in shaping cutting-edge security solutions for some of the most critical areas in technology, including cloud security and edge computing. He has held senior roles at leading organizations like Lacework, Google, Anomali, and Splunk where he built and led high-performing teams. Trevor is a prolific inventor with over 35 patents and pending patents, underscoring his deep expertise in risk management, data loss protection, and large-scale AI-driven security solutions. His leadership and forward-thinking approach continue to drive transformational results in the cybersecurity landscape.

Alex has over 20 years of experience building and leading product teams in delivering solutions securing organizations both large and small. Most recently, Alex served as VP of Product at LevelBlue / AT&T Cybersecurity where he led engineering and product management. Prior to acquisition by AT&T, Alex led product management for AlienVault where he served as VP, Product Management.

Barmak Meftah is globally recognized as one of the most successful leaders in enterprise software and cybersecurity, with a distinguished career marked by transformative leadership. Before founding Ballistic Ventures, he was the President of AT&T Cybersecurity, a position he took on following the successful acquisition of AlienVault. As CEO of AlienVault, he positioned the company as a market leader in unified security management and open-source threat intelligence. His strategic vision and leadership at AT&T Cybersecurity cemented its status as a top-five global managed security services provider. Barmak also served as Vice President of the Enterprise Security Products division at HP, following HP’s acquisition of Fortify Software, where he was the Chief Product Officer and one of the first employees. His career includes several senior management roles at Oracle, notably as head of products for the Oracle RDBMS for the Windows platform in the Server Technologies group. As General Partner at Ballistic, he mentors and guides startup CEOs through the complexities and challenges of building great teams and companies.

Roger Thornton is a driving force behind hundreds of technology products and services that have formed and grown companies across a range of industries. As a founder and CTO, his visionary product and technology leadership helped create cybersecurity industry leaders Fortify Software and AlienVault. As an investor, mentor and board member he has helped multiple generations of entrepreneurs build more than 15 successful cybersecurity companies. In his role as Co-founder and General Partner of Ballistic Ventures, Roger taps into over 30 years of experience and counsels future generations of cybersecurity founders who are focused on building great products as a foundation for great companies.

General Paul M. Nakasone, U.S. Army (retired) is one of the nation’s top experts in cybersecurity. Paul is from an Army family whose three generations of service dates back to World War II. His father served with the famed Military Intelligence Service during the Occupation of Japan. He spent nearly four decades in the United States Army, serving within the U.S., the Republic of Korea, Iraq, and Afghanistan. Paul concluded his career as the Director of the National Security Agency and Commander of the U.S. Cyber Command. This final assignment – spanning nearly six years – allowed him to lead the largest element of the U.S. Intelligence Community and Defense Department’s cyber forces during three national elections, a global pandemic, and increased threats to our homeland. Throughout his career, Paul brought innovative and transformative leadership to solve complex challenges.

In addition to his advisory role at Witness AI, Paul is the Founding Director of Vanderbilt University’s Institute of National Security, focused on building the next generation of leaders with the knowledge, skills, and abilities to succeed in a dynamic security environment, and serves on the OpenAI board of directors.

Karim has been with GV since its inception. He leads the firm’s investments in enterprise software and analytics as the IT stack reorganizes and learning algorithms extend our ability to gain insight from large amounts of data. Karim also has a passion for security innovation at a time when those technology shifts are continuously expanding vulnerable surface areas.

Before joining GV, Karim served on Google’s corporate development team and held business and product development positions at Level 3 Communications. Earlier in his career, Karim took on various product and marketing roles at Intel, initially on the i486 and later as product manager for the Pentium processor. He started his career at Siemens as a software engineer working on the first vehicle navigation system for BMW.

Karim is drawn to mission-driven founders with a healthy disregard for the impossible. “I find it very rewarding to team up at the early stages of challenging the status quo, and helping founders advance ideas into invaluable companies.”

He started partnering with entrepreneurs near the trough of the market in 2002 when he joined Atlas Venture. “Success was at a premium then,” he says, “I had to be a grounded optimist. The lessons learned from that period — through more failures than triumphs — were invaluable. I gained a deeper appreciation for the founder journey and what it takes to build an enduring business.”

Karim holds an MBA from Harvard Business School, an M.S. in electrical engineering from the University of Michigan, and a B.S. in computer engineering from Brown University, where he published several papers on neural networks.