Per-model status
Is Claude Haiku 4.5 watermarked?
No, Claude Haiku 4.5 does not watermark its text output as of August 2026, because it launched before Anthropic's August 2, 2026 watermarking cutoff. Anthropic has said it will retrofit watermarking to older models, so this is expected to change.
Haiku 4.5 shipped before the watermarking cutoff, so its output carries no statistical watermark today. A retrofit would apply only to output generated after that point.
FAQ
Is Claude Haiku 4.5 watermarked?
Not as of August 2026. Claude Haiku 4.5 launched before the August 2, 2026 cutoff, so its text output carries no statistical watermark today.
Can anyone detect Claude Haiku 4.5 output?
No. Anthropic announced a detection API but has not shipped it, and no third-party tool can read the statistical watermark. Even once it ships, only output from a marked model would be detectable.
Will Claude Haiku 4.5 get watermarked later?
Anthropic has said it is working to add watermarking to models released before the cutoff. If that happens, output generated after the retrofit would be marked, while text you generated before it would not be.
How do I remove the watermark if Claude Haiku 4.5 gets retrofitted?
A complete rewrite through a different, non-watermarking model breaks the statistical pattern. ClaudeRewrite does this automatically using DeepSeek V4 Flash, preserving your facts, numbers, and meaning.