Test shows invisible Unicode chars can remove Claude text watermarks

Available-Deer1723 · reddit · 2026-08-17

The author found that inserting invisible Unicode variation selectors is the only effective method to remove Claude text watermarks without destroying the text. Inserting them into 30% of characters drops the watermark score from 45 to below 1, and these characters survive normalization.

Tests showed that conventional editing like spell conversion or markdown stripping is ineffective. Additionally, code samples are barely watermarked due to their low entropy nature.

Related event: Study Finds Invisible Unicode Characters Can Strip Claude's Text Watermark(3 posts)→

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