Can bug splatter permanently damage clear coat?

Yes. Insect remains contain organic compounds that can stain or etch paint, particularly when baked onto hot panels for long periods. Prompt soaking and removal reduces the risk of permanent marking. Use a dedicated bug remover or a pre-wash soak to soften the residue before washing, and avoid scrubbing hardened remains, which can scratch the paint.

References
  1. Automotive paint, Wikipedia
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