🧭 Sony Music and Warner Chappell Sue Anthropic, Alleging a "Brazen Campaign" of Copyright Piracy

Sony Music Publishing, Warner Chappell Music, and a coalition of major music publishers filed suit against Anthropic in the U.S. District Court for the Northern District of California on August 29, 2026. The complaint accuses Anthropic of conducting a "brazen campaign of illegally torrenting, scraping, and downloading copyrighted works" to build Claude's training datasets — characterising the conduct as large-scale piracy rather than fair use.

Where this fits in Anthropic's mounting copyright litigation

This is the third major music-industry copyright action targeting Anthropic in 2026 alone:

• January 2026 — A cohort led by Concord Music Group and Universal Music Group sued for more than $3 billion over alleged illegal downloading of 20,000+ copyrighted songs, lyrics, and sheet music.
• Earlier 2026 — In the Bartz v. Anthropic authors' case, a judge ruled that while using copyrighted works for training may be defensible, acquiring that content through piracy is not. Anthropic was ordered to pay $1.5 billion in that action.
• August 29, 2026 — Sony Music Publishing, Warner Chappell, and additional publishers file the latest action, escalating pressure with a new theory centred on the method of acquisition rather than fair-use training arguments.

Anthropic said it will defend itself against the claims. The company has not publicly disclosed the data sources used to train Claude, a gap that prior courts have noted when ruling on discovery motions.

🧭 Claude Managed Agents: Domain-Level Web Filtering and Live Tool Swaps Without Agent Rebuilds

The September 2026 platform release notes add two complementary capabilities to Claude Managed Agents that significantly tighten control over agentic web access at runtime — without requiring a new agent version for either.

1. Domain-level filtering on web tools

You can now restrict which sites a Managed Agents session's web_search and web_fetch tools can reach. Set allowed_domains or blocked_domains on the tool's entry inside the agent_toolset_20260401 configs array:

# agent definition excerpt
{
  "agent_toolset_20260401": [
    {
      "type": "web_search",
      "config": {
        "allowed_domains": ["docs.anthropic.com", "github.com"],
        "user_location": {"country": "US", "region": "CA"}
      }
    },
    {
      "type": "web_fetch",
      "config": {
        "blocked_domains": ["pastebin.com", "hastebin.com"],
        "max_content_tokens": 8000
      }
    }
  ]
}

For compliance-sensitive deployments — financial services, healthcare, government — this lets you lock an agent to a curated set of approved sources and prevent data leakage to arbitrary external endpoints, all declared at the tool-config level rather than enforced by prompt instructions (which can be bypassed).

2. Mid-session tool updates

You can now call the session-update endpoint to patch a running session's agent.tools and agent.mcp_servers — including their permission policies and per-tool web settings — without ending the session or creating a new agent version:

# Python SDK — update domain filters mid-session
client.beta.managed_agents.sessions.update(
    session_id=session_id,
    agent={
        "tools": [
            {
                "type": "web_search",
                "config": {"allowed_domains": ["internal.company.com"]}
            }
        ]
    }
)
# Updated allowed_domains apply immediately to the rest of this session

🧭 Anthropic Corrects Its Claude Code Limits Post — 17% Weekly Cut Arrives September 14

The +50% weekly usage boost that Claude Code Pro, Max, Team, and legacy seat-based Enterprise users received on May 13, 2026, expired at 11:59 PM PT on August 31 — its third extension having run its course. What users didn't expect was Anthropic's follow-up correction.

The retraction

Anthropic initially posted that weekly limits would simply return to their pre-boost baseline once the extension ended, implying a flat reset. The post was deleted and republished with a correction: limits will not merely revert — they will drop 17% below the pre-boost baseline, effective September 14, 2026. The two-week gap between September 1 and September 14 gives users time to adjust pipelines and evaluate usage patterns before the cut lands.

What the numbers mean in practice

The +50% boost temporarily pushed weekly limits to 1.5× their prior baseline. On September 1 they return to 1.0×. On September 14 they fall to approximately 0.83× of that same baseline — meaning the net drop from the boosted peak is about 45%.

• The 5-hour rolling session limit is not affected by either change.
• API-direct users billing against tokens are unaffected — the limits apply only to claude.ai-hosted Claude Code sessions on subscription plans.
• Anthropic cited continuing high demand relative to capacity as the reason for the reduction, consistent with earlier messaging that the boost was provisional.