According to @StockMKTNewz, OpenAI is presented with a $500B market cap among top global companies, alongside Exxon Mobil (XOM) at $508B, Johnson & Johnson (JNJ) at $500B, and Palantir (PLTR) at $450B, source: @StockMKTNewz. The post states OpenAI is the 21st largest company, while its accompanying list shows OpenAI at No. 22 behind JNJ, source: @StockMKTNewz. For trading context, the source’s snapshot places OpenAI’s reported size near XOM and JNJ, framing relative market cap comparisons in the AI equity landscape, source: @StockMKTNewz.

According to @StockMKTNewz, the most valuable U.S. company by market capitalization progressed as follows: 2005 General Electric; 2006-2011 Exxon Mobil; 2012-2017 Apple; 2018 Microsoft; 2019-2024 Apple; 2025 Nvidia, source: X post by @StockMKTNewz on Sep 26, 2025, https://twitter.com/StockMKTNewz/status/1971377466494042529. For traders, this timeline highlights a shift in market leadership from energy to consumer-tech platforms and now to AI-focused semiconductors, an inference directly drawn from the leadership sequence, source: X post by @StockMKTNewz on Sep 26, 2025, https://twitter.com/StockMKTNewz/status/1971377466494042529. Crypto market angle: while the source does not mention digital assets, the 2025 leadership listing of Nvidia underscores AI as the prevailing macro theme that crypto traders may monitor for risk sentiment context, source: X post by @StockMKTNewz on Sep 26, 2025, https://twitter.com/StockMKTNewz/status/1971377466494042529.