** Oppenheimer downgrades Goldman Sachs GS.N, Jefferies Financial Group JEF.N and Carlyle Group CG.O to "perform" from "outperform"

** Expects investment banking revenue to stay flat for the rest of 2025, compared to an earlier forecast of a 32% jump; sees challenges in monetizing investments for CG

** Shares of Goldman GS.N, Carlyle CG.O and Jefferies JEF.N down between 0.36% and 0.79% in premarket trading

**Jefferies, scheduled to report Q1 results next week, will offer a peak into investment banking performance in the first three months of the year

** Up to last's close, GS, JEF, CG down ~3.64%, 25.43%, 16.42%, respectively

(Reporting by Akriti Shah in Bengaluru)

((akriti.shah@thomsonreuters.com))