Menlo Park, Calif. -- Sequoia Capital, the Menlo Park-based venture capital firm, has led a new $34.5 million round of funding for Bit9, a Massachusetts-based developer of security tools designed to detect and prevent sophisticated malware and cyber threats. Previous backers Atlas Venture, Highland Capital Partners, Kleiner Perkins Caufield & Byers and .406 Ventures also participated in the company's fourth round, which it will use to fund new product development efforts and expand sales and marketing activities. The round is the largest in company history. "It places a bet squarely on our vision and technology," said Patrick Morley, the president and CEO of Bit9. "It's an exciting time as we are dramatically changing how organizations protect themselves from IP theft and advanced attacks by focusing on a trust-based approach." Currently, Bit9 protects more than 700 organizations across industry segments such as education, finance, government, healthcare, retail and utilities.