OpenAI

In late February 2026 OpenAI says ChatGPT has surpassed 900 million weekly active users and roughly 50 million paying subscribers, with January and February its largest-ever months for new subscribers.

Announced in February at $110B and closed on March 31, 2026 at $122B and an $852B post-money valuation — the largest private funding round ever. Amazon committed up to $50B (a large portion contingent on an IPO or AGI milestone), with Nvidia and SoftBank each investing $30B.

On April 23, 2026 OpenAI releases GPT-5.5, positioned as its 'smartest and most intuitive model yet' with agentic-first training; it becomes the default ChatGPT model in early May.

On June 26, 2026 OpenAI introduces the GPT-5.6 family — Sol (flagship), Terra (balanced) and Luna (fast/low-cost) — in a staggered, limited release after the U.S. administration requested controlled access on national-security grounds, with broader availability to follow.

On July 9, 2026 OpenAI moved its GPT-5.6 series — Sol (flagship, tuned for demanding domains like biology, chemistry and cybersecurity), Terra (balanced mid-tier) and Luna (fastest/cheapest) — from a government-gated preview to general availability for all users. Preview API pricing runs $5/$30 per million input/output tokens for Sol, $2.50/$15 for Terra and $1/$6 for Luna, with a Sol Fast mode on Cerebras reaching up to 750 tokens per second.

On July 9, 2026 OpenAI launched ChatGPT Work, an agent inside ChatGPT that gathers context across a user's connected apps, breaks a goal into steps and works autonomously for hours to return finished spreadsheets, slides, documents and interactive web apps rather than chat replies. Powered by the newly broadened GPT-5.6 family, it follows the same usage structure as OpenAI's Codex, which is folding into a single ChatGPT desktop app, as OpenAI escalates the agentic-AI race against rivals.

On July 10, 2026 Apple filed suit in California federal court accusing OpenAI, its hardware chief Tang Tan (a former Apple VP), and Jony Ive's OpenAI-owned io Products of a coordinated campaign to steal trade secrets about Apple's unreleased hardware. The complaint alleges OpenAI pushed Apple employees and job candidates to bring components, drawings and 'actual parts' to interviews, and that a departing engineer kept an Apple laptop loaded with confidential documents. Apple seeks to bar OpenAI from using the material and force its return.

In January 2025 OpenAI, SoftBank, Oracle and MGX announce Stargate, a joint venture to invest up to $500B over four years in U.S. AI data-center infrastructure.

OpenAI acquires io — the device startup co-founded by former Apple designer Jony Ive — for ~$6.5B in equity to build AI-native consumer hardware, and in August 2025 releases GPT-5, its fifth-generation flagship.

On October 28, 2025 OpenAI completes its restructuring: the nonprofit, renamed the OpenAI Foundation, controls the for-profit OpenAI Group PBC (a Delaware public benefit corporation). Microsoft holds roughly 27% and commits to buy an incremental $250B of Azure services.

OpenAI releases the natively multimodal GPT-4o in May 2024 and, in September, the o1 family — its first 'reasoning' models that think step-by-step before answering.

OpenAI launches GPT-4 on March 14, 2023 — its first broadly multimodal model — via the API and ChatGPT Plus, setting a new bar for reasoning and professional-exam performance.

On November 17, 2023 the board abruptly fires CEO Sam Altman; after overwhelming employee and Microsoft pressure he is reinstated five days later with a reconstituted board — a defining governance episode for the company.

OpenAI releases ChatGPT on November 30, 2022. It reaches 100M users within two months, becoming the fastest-growing consumer application in history at the time and igniting the generative-AI boom.

OpenAI creates a 'capped-profit' for-profit subsidiary and Microsoft invests $1B, moving OpenAI's training and inference workloads onto Azure and beginning a deep multi-year partnership.

OpenAI is launched on December 8, 2015 by Sam Altman, Elon Musk, Greg Brockman, Ilya Sutskever and others, with $1B pledged and a mission to ensure that artificial general intelligence benefits all of humanity.