The stock market closed lower on Friday, as investor sentiment weakened amid rising oil prices driven by supply concerns in the Middle East, higher Treasury yields, and uncertainty surrounding technology and AI investments.
Brent crude climbed 3.1%, surpassing $116 per barrel amid ongoing supply concerns, while the yield on the 10-year US Treasury note neared 4.99%, adding further pressure on equities.
Overall, S&P 500 fell 0.5% to 7,624, while Nasdaq slid 0.2% to 25,955.
Chart of the Day
Here is the one-year chart of Rubrik (RBRK) as of September 28, 2026, when the stock was at $113.
Rubrik, the Security and AI Operations company, is building a new AI security business as companies begin deploying AI agents across their operations. Management stated these agents can access sensitive data and take actions on their own, creating new security risks that traditional tools were not designed to handle.
Rubrik Agent Cloud (RAC) is Rubrik’s platform for securing and controlling AI agents, helping companies see what their agents are doing and stop them from taking actions that break security rules. Management stated it is built around three pillars: monitoring AI agents, controlling their actions through security and governance rules, and Agent Rewind, which lets customers undo harmful actions. The product already had more than 15 paying customers, with proof-of-concept projects starting to move into full production, including a healthcare customer using it to securely expand its use of AI while protecting sensitive data.
Rubrik is building all of this into a single platform so customers can manage AI visibility, identity, security and recovery without having to buy several separate tools.
RBRK is on the radar for the Growth Portfolio.
