Yahoo has a list of services it provides to government agencies. (warning: that list may be taken down at some point). They'll provide your emails, account information, IP address you've logged in from etc. etc. And each service has a price.
This list was leaked from inside Yahoo and is now available online.
Yahoo has decided to use copyright law to make Cryptome take the document down.
This seems, to me, to be an unbearable stretch of copyright law. Copyright was intended to protect authors from having people copy their works and resell them without paying royalties. Copyright law was not intended to let corporations keep their businesses secret.
The telling point comes in part of the takedown notice as quoted at Wired.com.
“Therefore, release of Yahoo!’s information is reasonably likely to lead to impairment of its reputation for protection of user privacy and security, which is a competitive disadvantage for technology companies,” the company added.
Paraphrasing: Don't tell the truth about us. Our customers won't like it.
If the truth is going to impair your reputation, you really shouldn't be complaining about the messenger. But then, Yahoo is a corporation, so what else should one expect?