Are spam filters biased against new senders?

Spam filters are appropriately cautious with new senders, but this is not bias in the prejudicial sense. It reflects the reality that unknown senders have no track record to evaluate.

New IPs and domains face heightened scrutiny because many spam operations use fresh infrastructure to evade filters. Without history, filters cannot distinguish legitimate new senders from spam operations.

This caution manifests as stricter filtering, lower sending limits, and more aggressive responses to any problems. New senders must prove themselves through clean behavior.

The solution is warming: gradually building volume while maintaining excellent engagement and avoiding any issues. This establishes the positive track record that ends the initial caution.

Once reputation is established, new senders are treated fairly. The initial caution is temporary, not permanent.

Filters are skeptical of strangers, as any prudent gatekeeper would be. Demonstrate trustworthiness, and skepticism fades.