Autumn 2025: A Season of Major Launches
Before the arrival of Claude Opus 4.5, Anthropic made a series of announcements throughout the autumn of 2025. A look back at the key moments of this intense period.
Claude Sonnet 4.5 โ The King of Code
September 29, 2025 โ Anthropic launches Claude Sonnet 4.5, presented as โthe best coding model in the worldโ.
Key Performance
| Benchmark | Score |
|---|---|
| SWE-bench Verified | 77.2% |
| OSWorld (computer use) | 61.4% |
Features
- Complex Agents โ Maintains focus for 30+ hours
- Computer Use โ Leader on computer use benchmarks
- Reasoning โ Substantial gains in math and logic
Pricing
| Type | Price |
|---|---|
| Input | $3 / million tokens |
| Output | $15 / million tokens |
Associated Product News
- Claude Code โ Checkpoints and rollback
- VS Code โ Native extension
- Claude for Chrome โ Available for Max users
- Claude Agent SDK โ Developer toolkit to build agents
Introducing Claude Sonnet 4.5โthe best coding model in the world.
โ @claudeai on X
Claude Haiku 4.5 โ Speed and Efficiency
October 15, 2025 โ Launch of Claude Haiku 4.5, Anthropicโs compact model.
The Best Price/Performance Ratio
| Metric | Value |
|---|---|
| SWE-bench Verified | 73.3% |
| Speed | 2-4.5x faster than Sonnet 4.5 |
| Cost | 1/3 the price of Sonnet |
Pricing
| Type | Price |
|---|---|
| Input | $1 / million tokens |
| Output | $5 / million tokens |
Optimal Use Cases
- Real-time applications, low latency
- Chat assistants and customer service
- Pair programming and rapid prototyping
- Multi-agent orchestration with Sonnet 4.5
- Computer vision applications
Microsoft Partnerships
November 18, 2025 โ Triple announcement with Microsoft.
Claude in Microsoft Foundry
Claude models are now available in Microsoft Azure AI Foundry, offering enterprises easy access via the Microsoft ecosystem.
Claude in Microsoft 365 Copilot
Integration of Claude directly into Microsoft productivity tools used daily by hundreds of millions of people.
Strategic Partnership with NVIDIA
Tripartite collaboration Microsoft-NVIDIA-Anthropic to accelerate AI infrastructure.
Claude Desktop
October 21, 2025 โ General availability of Claude Desktop.
Claude Desktop is now generally available. New on Mac: Capture screenshots, click windows to share context, and press Caps Lock to talk to Claude aloud.
โ @claudeai on X
New Mac Features
- Screenshot โ Visual context sharing
- Window Clicking โ Context selection by pointing
- Voice Control โ Caps Lock to talk to Claude
- Parallel Sessions โ Local and remote
Guide: Using CLAUDE.md Files
November 25, 2025 โ The Claude blog publishes a guide on customizing Claude Code via CLAUDE.md files.
Concept
A CLAUDE.md file at the root of the repo provides persistent context to Claude Code:
- Project architecture
- Code standards
- Team workflows
- Build/test commands
Key Points
| Feature | Description |
|---|---|
/init | Automatically generates a CLAUDE.md |
| Custom commands | Create commands in .claude/commands/ |
| Subagents | Isolate context by work phase |
| MCP servers | Document Model Context Protocol integrations |
Other Notable Announcements
Geographic Expansions
| Date | Announcement |
|---|---|
| Oct 7 | Office in India (2nd in Asia-Pacific) |
| Oct 23 | Office in Seoul (3rd in Asia-Pacific) |
| Oct 29 | Office in Tokyo + MoU with Japan AI Safety Institute |
| Nov 7 | Offices in Paris and Munich |
Enterprise Partnerships
| Date | Partner | Detail |
|---|---|---|
| Oct 6 | Deloitte | 470,000 people with access to Claude |
| Oct 14 | Salesforce | Expansion to regulated industries |
| Nov 4 | Cognizant | 350,000 employees with access |
Sector Programs
- Oct 20 โ Claude for Life Sciences
- Oct 27 โ Claude for Financial Services
1 Million Tokens
August 12, 2025 โ Claude Sonnet 4 now supports 1 million tokens of context.
Process over 75,000 lines of code or hundreds of documents in a single request.
โ @claudeai on X
Visual Timeline
August 2025
โโโ 12 - Sonnet 4: 1M context tokens
September 2025
โโโ 15 - Claude in Xcode
โโโ 29 - Claude Sonnet 4.5
October 2025
โโโ 6 - Deloitte Partnership
โโโ 7 - India Office + CTO Rahul Patil
โโโ 14 - Salesforce Extension
โโโ 15 - Claude Haiku 4.5
โโโ 20 - Claude for Life Sciences
โโโ 21 - Claude Desktop GA
โโโ 23 - Seoul Office + Google Cloud TPUs
โโโ 27 - Claude for Financial Services
โโโ 29 - Tokyo Office
November 2025
โโโ 4 - Cognizant + Iceland education pilot
โโโ 7 - Paris & Munich Offices
โโโ 12 - $50B infrastructure USA
โโโ 13 - Maryland + AI espionage disruption
โโโ 18 - Microsoft Foundry & 365 Copilot
โโโ 24 - Claude Opus 4.5
โโโ 25 - Guide CLAUDE.md filesKey Takeaways
Autumn 2025 established the foundations for Anthropicโs dominance:
- Models โ Sonnet 4.5 and Haiku 4.5 cover all use cases
- Distribution โ Microsoft, Salesforce, Deloitte = massive access
- International โ Physical presence on 3 continents
- Products โ Claude Desktop and Claude Code mature
All this prepares for the arrival of Opus 4.5 on November 24.