Are downloadable files safe?

Some store owners worry about uploading files to their site. WooCommerce uses a few different technologies to prevent users from pirating your files (https://docs.woocommerce.com/document/digital-downloadable-product-handling/).

In addition, any files you upload will be hidden from search engines.

For the most part, it isn't worth a ton of effort to prevent piracy. If a user really wants to pirate your content, they'll find a way to do so. But you can always limit downloads and add an expiry time.

One way to protect PDF is with PDF stamping (https://woocommerce.com/products/woocommerce-pdf-watermark/). This embeds personal user information in the PDF (in very small, hard-to-notice print). This way, you have some idea of who shared the original document. This PDF stamping product is a premium plugin, but there are also free solutions on the market.