No, Panther does not charge for logs that fail to classify during ingestion. You are only charged for logs that are successfully classified.
For more detailed information about Panther's ingestion process, usage limits, log filtering, and cost management, please refer to the following resources:
Can I use Ingestion Filters to reduce Panther ingestion costs?
Can I exclude logs or specific fields from ingestion into Panther?
If you have any further questions about Panther's pricing or ingestion process, please don't hesitate to contact our support team.