US markets opened with gains on December 19, as the Dow Jones Industrial Average rose 0.19%, the S&P 500 increased 0.28%, and the Nasdaq Composite climbed 0.51%. Tech stocks led the rally, with Oracle surging 5.3% and Nvidia rising 1.5% at the open. On-chain data highlights strong early momentum in the tech sector, with trading volumes and price movements closely matching pre-market expectations.