Dropbox DMCA takedown in personal private folder

We've known since last year that Dropbox will block public links to files that are infringing on copyright, and for a brief tweet moment, it seemed that they could do more than that. This here screendump makes it look like they can delete the files too, as Darrel Whitelaw discovered this message in his personal folder...

Like whoah whoah whoah, how did that happen? Did Dropbox go through all of Darrel's personal files to check if he had a copy of Snow White lying around? If he was stuffing his personal box full of the latest Johnny Cash album? No, it seems that a scanning against DMCA actionable materials only happens when a link is generated, and Darrel does say that he created a link. And the magic of searching for copyrighted material comes from file hashes. Legal submits hashes, and share-link files are scanned against hashes. Aren't computers grand? They do so much, so fast. So even if Darrel only made one share link and showed his buddy said link, and it wasn't public like posted on Reddit... The file could have the same hash as a file that was public previously, and the hash is what triggers the DMCA.

wow. @dropbox DMCA takedown in personal folders . . . this is new to me. pic.twitter.com/fSKxJUrFus

— darrell whitelaw (@darrellwhitelaw) March 30, 2014

What happens to the DMCA'ed file? Is it gone, deleted? Darrel says it's only disabled from being shared - *PHEW* - so lets not panic about false positives yet. Your personal files won't be deleted. Cool?

@SELOBrien @Dropbox @wilw disable sharing

— darrell whitelaw (@darrellwhitelaw) March 30, 2014

Dropbox were quick to respond to Darrel too, albeit not as quick as the rest of twitter.

@darrellwhitelaw Hey Darrel - content removed under DMCA only affects share-links. DM us if you’re seeing something different so we can help

— Dropbox Support (@dropbox_support) March 30, 2014