Check out the companies making headlines before the bell. United States Steel — The industrial stock plunged 6% after Vice President Kamala Harris opposed the planned sale of United States Steel to Japan’s Nippon Steel. She made these statements during a Labor Day rally in front of union members in Pittsburgh, Pennsylvania, where she said that United States Steel was “an historic American company and it is vital for our country to maintain strong American steel companies.” Boeing — Shares slipped 3% after Wells Fargo downgraded the aircraft maker to underweight from equal weight. Analyst Matthew Akers cited the company’s peaking free cash flows as a reason for the downgrade. Unity Software — The video game maker rallied 6% after Morgan Stanley upgraded the stock to overweight from equal weight. The bank pointed to Unity’s position as “the clear game engine” and derisked forward estimates as catalysts for the stock. NetApp — The data storage stock added 1.6% following an upgrade to buy from hold at Loop Capital. Loop analyst Ananda Baruah listed several catalysts, including NetApp’s cloud storage software partnerships and a recent pullback. Novartis — Shares were down 1.7% following a Jefferies downgrade to hold from buy. Analyst Peter Welford noted that although he’s optimistic in the pharmaceutical stock’s long-term trajectory, Novartis will need time into 2025 to ramp up its approvals. Bank of America — The bank stock was down fractionally. Warren Buffett’s Berkshire Hathaway, which began cutting its holdings of Bank of America this summer, revealed Friday it sold more shares last week. Merck — The pharmaceutical giant announced Tuesday that the European Commission has approved a combination of drugs including Merck’s Keytruda as a treatment for bladder cancer. Shares of Merck were little changed. — CNBC’s Michelle Fox and Jesse Pound contributed reporting.