Attention Is All You Need (Transformer paper)

Vaswani et al. (Google Brain and Google Research) publish the Transformer architecture in the paper Attention Is All You Need. The architecture replaces recurrence with self-attention and becomes the foundation for every subsequent frontier model (GPT, BERT, Claude, Gemini, Llama).

OpenAI GPT-1

OpenAI releases the first Generative Pre-trained Transformer (117M parameters), demonstrating that a single pre-trained Transformer plus task-specific fine-tuning could match purpose-built NLP models. Precursor to the scaling thesis.

OpenAI GPT-3 release

GPT-3 (175B parameters) released via API. First model to demonstrate strong few-shot in-context learning at scale. Triggers the modern generative AI boom and underpins the OpenAI-Microsoft commercial partnership.

ChatGPT launch

OpenAI releases ChatGPT as a free research preview on November 30. Reaches 1M users in 5 days and approximately 100M monthly active users by Jan 2023, the fastest consumer product adoption curve to date. Catalyzes the generative AI investment wave.

Microsoft $10B commitment to OpenAI

Microsoft announces a multi-year, multi-billion-dollar investment in OpenAI on January 23, reportedly $10B. Cements Azure as OpenAI's exclusive cloud provider and makes Microsoft the largest commercial backer.

OpenAI GPT-4

GPT-4 released March 14. Multimodal input (image + text), substantially stronger reasoning, professional-exam benchmarks. Becomes the de facto frontier reference for two years.

Meta Llama 2 (open-weights)

Meta releases Llama 2 (7B, 13B, 70B) on July 18 with a commercial-permissive license. First credible open-weights alternative at frontier-adjacent quality. Begins the open-weights pressure on closed-API margins.

Amazon $4B commitment to Anthropic

Amazon announces an initial $1.25B investment with an option to expand to $4B on September 25. Trainium and Inferentia chip integration plus AWS as primary cloud. Expanded to $8B total in November 2024.

EO 14110 (Biden AI Executive Order)

Biden Executive Order 14110 signed October 30 establishes federal AI risk management, NIST testing requirements, and a reporting threshold for dual-use foundation models trained above 10^26 FLOPs. Subsequently rescinded by EO 14179 in January 2025.

OpenAI DevDay and Sam Altman ouster + reinstatement

OpenAI hosts DevDay November 6 launching GPTs (custom assistants), Assistants API, and lower pricing. Eleven days later (Nov 17 to 22) the board fires Sam Altman and reinstates him after employee revolt. Major governance event with downstream consequences for OpenAI structure.

Anthropic Claude 3 family

Claude 3 (Haiku, Sonnet, Opus) released March 4. Opus matches or exceeds GPT-4 on most benchmarks. Establishes Anthropic as a credible second frontier lab on capability, not only on safety positioning.

Microsoft acqui-hires Inflection AI

Microsoft hires Mustafa Suleyman, Karen Simonyan, and most of the Inflection team. Pays Inflection approximately $650M license fee. Structured to avoid merger filing; triggers FTC and EU inquiries (closed without action by Q1 2025).

Meta Llama 3 release

Meta releases Llama 3 (8B, 70B) April 18, with the 405B variant following in July 2024. Continues open-weights pressure; 70B competitive with GPT-4 on multiple benchmarks.

NVIDIA acquires Run:ai

NVIDIA announces acquisition of Run:ai (GPU orchestration software for Kubernetes) on April 24 for approximately $700M. Post-close, NVIDIA open-sources the platform. FTC reviewed; closed without action December 2024.

OpenAI GPT-4o and Google Gemini 1.5 Pro general availability

OpenAI launches GPT-4o May 13 with native multimodal (text, vision, audio) and substantially lower latency. Google's Gemini 1.5 Pro reaches general availability around the same window with a 1M-token context. Inflection point for multimodal product surfaces.

xAI Series B at $24B with Colossus plan

xAI raises $6B Series B in May 2024 at a $24B post-money. Funds Colossus supercluster in Memphis (100K H100 cluster brought online by Q3 2024). Begins the xAI infrastructure-scaling thesis.

Amazon acqui-hires Adept AI

Amazon hires David Luan and most of the Adept research team into a new AGI org under Rohit Prasad on June 28. Pays an undisclosed license fee. FTC and EU inquiries opened, both closed without action by Q1 2025.

EU AI Act enters into force

Regulation (EU) 2024/1689 enters into force August 1, 2024. Phased rollout follows: prohibited-AI bans from February 2025; General Purpose AI obligations from August 2025; high-risk system obligations from August 2026; embedded-product obligations from August 2027.

Google acqui-hires Character.AI

Google pays approximately $2.7B for a non-exclusive license to Character.AI plus to hire founders Noam Shazeer and Daniel de Freitas back into DeepMind. Character.AI continues to operate as a standalone consumer product with new leadership. Triggers FTC, EU, and UK CMA inquiries (downgraded by mid 2025).

OpenAI o1 (reasoning model series)

OpenAI launches o1-preview and o1-mini September 12, introducing inference-time chain-of-thought reasoning. First major frontier release with explicit test-time compute scaling, setting a new architectural axis beyond raw parameter count.

OpenAI $6.6B Thrive-led round at $157B

OpenAI closes a $6.6B primary round on October 2 led by Thrive Capital, alongside a concurrent secondary tender. Investors include Microsoft, NVIDIA, SoftBank, Khosla, Altimeter, Fidelity, Tiger Global, and MGX.

Nebius direct listing on Nasdaq

Nebius Group (formerly Yandex N.V. after divesting its Russian businesses in July 2024) resumes Nasdaq trading on October 21 under ticker NBIS. Becomes a public GPU cloud peer to CoreWeave.

Amazon $4B Anthropic follow-on (total $8B)

Amazon adds $4B to its Anthropic commitment on November 22, bringing the total to $8B. AWS becomes Anthropic's primary training partner; Trainium and Inferentia integration deepens.

OpenAI o3 announcement

OpenAI announces o3 at the close of the 12-day December launch event. ARC-AGI breakthrough scores (87.5 percent on semi-private set, well above prior 30 percent state of art). General availability follows in early 2025.

Databricks $10B Series J at $62B

Databricks closes a $10B primary round on December 17 led by Thrive Capital. Largest VC software round prior to OpenAI 2025-Q1. Funds AI product roadmap (Mosaic, agent platform) and provides pre-IPO employee liquidity.

DeepSeek-R1 release

DeepSeek (China) releases R1 on January 20 with open weights and an MIT license. Reasoning-class capability competitive with o1 at fraction of training cost. Triggers a brief NVDA selloff and accelerates open-weights commoditization narrative.

EO 14179 rescinds EO 14110

Trump Executive Order 14179 (January 23) rescinds Biden EO 14110. Federal AI regulatory posture shifts toward lighter-touch oversight. State laws (California AB 2013, Colorado AI Act) fill the federal gap.

Stargate project announcement

OpenAI, SoftBank, Oracle, and MGX announce Stargate on January 21: a planned $500B over four years investment in US AI infrastructure, with $100B deployed immediately. First Stargate site in Abilene, Texas.

OpenAI $40B SoftBank-led round at $300B

OpenAI closes the largest private financing in history on March 31: $40B at a $300B post-money, led by SoftBank with Microsoft, Coatue, Altimeter, and Thrive. Funds Stargate compute commitments and continued frontier training.

CoreWeave IPO

CoreWeave prices its IPO on March 27 at $40 per share (below the marketed range), raising approximately $1.5B at a $23B initial valuation. First major AI infrastructure IPO. NVIDIA agrees to backstop $250M of the offering.

Google announces Wiz acquisition for $32B

Google announces agreement to acquire cloud security platform Wiz for $32B on March 18. Largest software deal in Google history. Wiz CEO Assaf Rappaport reversed his 2024 rejection of the earlier $23B offer. Pending DOJ antitrust review.

Meta Llama 4 release

Meta releases Llama 4 (Scout, Maverick, and Behemoth tiers) April 5. Native multimodal, 10M-token context on Scout, mixture-of-experts architecture. Continues Meta's open-weights pressure on closed labs.

Anthropic Claude 4 family (Opus 4, Sonnet 4)

Anthropic releases Claude Opus 4 and Sonnet 4 on May 22, with strong gains in coding (SWE-bench Verified) and agentic tool use. Opus 4 becomes a primary frontier reference for coding agents (Cursor, Windsurf, GitHub Copilot Workspace).

Meta acquires 49 percent of Scale AI

Meta acquires 49 percent non-voting stake in Scale AI on June 13 for approximately $14.3B (implied valuation approximately $29B). Founder Alexandr Wang joins Meta as Chief AI Officer. Treated by regulators as a de facto talent acquisition; FTC opens inquiry but no enforcement as of 2026-Q1.

OpenAI GPT-5

OpenAI releases GPT-5 August 7. Unifies the reasoning-model line (o-series) and the chat line into a single model with adaptive reasoning depth. Becomes the default ChatGPT model for free and paid users.

EU AI Act GPAI obligations apply

General Purpose AI provider obligations under the EU AI Act take effect August 2, 2025. Frontier-lab compliance work intensifies. Codes of practice signed by most major providers (OpenAI, Anthropic, Google, Mistral, Meta with carve-outs).

Colorado AI Act effective

Colorado SB24-205 Consumer Protections for Interactions with Artificial Intelligence Systems takes effect February 1, 2026. First comprehensive US state AI regulation. Requires risk management for high-risk consequential decisions.

EU AI Act high-risk rules apply (planned)

Phase 3 of EU AI Act rollout: high-risk system obligations (Annex III) apply from August 2, 2026. Affects AI used in employment, credit, education, critical infrastructure, law enforcement.

EU AI Act embedded-product rules apply (planned)

Phase 4 of EU AI Act rollout: high-risk AI embedded in safety components of regulated products (machinery, medical devices, in-vitro diagnostics, vehicles) apply from August 2, 2027.