Obsidian Security raised $85 million in a Series D round at a $1.1 billion valuation, the Palo Alto-based company announced on August 4, 2026, crossing into unicorn territory as enterprises race to govern the AI agents they are deploying across their software stacks. Crescent Cove Advisors led the round, with participation from all of the company’s existing investors, including Greylock Partners and Menlo Ventures. The raise pushes Obsidian’s total funding past $200 million. The round arrives…