> Even simpler: do not upload copyrighted materials to Dropbox, Google Drive, etc.
Everything is copyrighted. The comment you just wrote is automatically copyrighted. "Do not upload copyrighted materials" means you can only upload things made over a century ago (which either were made before copyright existed, or were copyrighted but their copyright expired). Want to upload your vacation photos? Too bad, they were made this year, so they are copyrighted, and will be copyrighted for several decades after you're already dead.
No, you have licensed your content to Y Combinator. It’s in the TOS:
> By uploading any User Content you hereby grant and will grant Y Combinator and its affiliated companies a nonexclusive, worldwide, royalty free, fully paid up, transferable, sublicensable, perpetual, irrevocable license to copy, display, upload, perform, distribute, store, modify and otherwise use your User Content for any Y Combinator-related purpose in any form, medium or technology now known or later developed.
Everything is copyrighted. The comment you just wrote is automatically copyrighted. "Do not upload copyrighted materials" means you can only upload things made over a century ago (which either were made before copyright existed, or were copyrighted but their copyright expired). Want to upload your vacation photos? Too bad, they were made this year, so they are copyrighted, and will be copyrighted for several decades after you're already dead.