Brendan Hannigan

Entrepreneur Partner

Brendan has been affiliated with Polaris since 2001, working with multiple portfolio companies. After a successful sale and integration of Polaris-backed Q1 Labs to IBM, Brendan joined Polaris Partners in 2016 as entrepreneur partner. Brendan served as Chairman of the Board of Polaris-backed Twistlock until its successful sale and exit to Palo Alto Networks in 2019. He is currently co-founder and CEO of Polaris-backed Sonrai Security and is a board member of Tausight, a Polaris healthcare IT portfolio company.

Brendan was previously the general manager of IBM Security. Under Brendan’s leadership, IBM Security grew significantly faster than the overall security market to become the number one enterprise security provider in the world with almost $2B of annual revenue.

Prior to IBM, Brendan served as president and CEO of Q1 Labs, a pioneer and leader in the security intelligence and analytics market. For over eight years, from 2003 to 2011, Brendan held a variety of executive positions, including executive vice president of marketing and engineering, COO, president, and eventually CEO.

Earlier in his career Brendan was director of network research at Forrester Research where he oversaw the firm’s most successful practices, covering enterprise networks, security technology and public network services. Before Forrester, Brendan served in a variety of senior engineering roles at Digital Equipment Corp., Wellfleet Communications, and Motorola.

Brendan graduated with honors in computer science from University College Dublin in Ireland.

This website is not an advertisement. This website is intended solely to provide general business information on Polaris Partners and any affiliates thereof (collectively, “Polaris”). Nothing on this website should be construed as an offer of investment advisory services by Polaris or a solicitation or an offer of interests in any Polaris fund. Visitors to this website are not to construe the contents of this website or any prior or subsequent communication from Polaris or any of its representatives, as legal, tax or investment advice. References to specific companies are for illustrative purposes only and do not represent all of the companies recommended for advisory clients. Such references are not intended to be, and should not be interpreted as, recommendations or investment advice. All information has been obtained from sources believed to be reliable, but its accuracy is not guaranteed, and Polaris disclaims any duty to update any of the information and data contained herein. Certain statements may be deemed forward-looking, but any such statements are not guarantees of any future performance and actual results or developments may differ materially from those discussed. There is no guarantee that investment objectives will be achieved or that any particular investment will be profitable. Past performance does not guarantee future results. Where applicable, figures include investments made directly and indirectly by the Polaris Main Funds and may include co-investments with the Polaris Growth Funds and the Polaris Innovation Funds. Please see the complete list of investments here, as well as the Terms of Use for additional information and disclosures.


The endorsements of current or past portfolio company executives are provided as illustrative examples and designed to demonstrate the benefits to portfolio companies of partnering with us. These statements are primarily aimed at prospective portfolio companies and not intended to solicit investors. The portfolio companies covered in these endorsements do not represent all portfolio company investments we have made. The experiences highlighted in these testimonials are solely those of the executives profiled and may not necessarily represent or be indicative of the current, past, or future experiences of other portfolio companies. Past results and experiences discussed are not indicative, or a guarantee of future results and experiences. We have not provided cash or other type of compensation in exchange for receiving these endorsements. We do not believe there are typically any material conflicts associated with providing these endorsements. The compensation of our portfolio company executives is primarily driven by the performance of their respective portfolio companies and any discretion we exercise in such compensation determinations is not influenced by whether an executive has provided a favorable statement. Additionally, the economic interests of our portfolio companies’ executives are generally well-aligned with ours and those of our investors. Nevertheless, the fact that these endorsements have been provided by individuals whose compensation we exercise a certain level of control over may incentivize them to provide favorable evaluations of their experiences working with us.