A prominent leaker who revealed announcements from Nintendo and sent a cease & desist in order to prevent them from leaking information from the Nintendo Direct.
A Twitter named Sabi has been revealing announcements for E3 2019 over the past few days, almost all of which have come true. Sabi correctly predicted that remastered for modern systems.
It seems that Nintendo's lawyers are not to be underestimated, as Sabi put up a post on Twitter stating that they wouldn't be revealing any more leaks that concern Nintendo games. The fearsome lawyers at Nintendo had somehow managed to discover Sabi's true name and address and sent them a cease & desist letter. Sabi has complied with Nintendo's request and has only been posting leaks about other developers and publishers.
Sabi spoke to Kotaku in greater detail about the circumstances surrounding the cease & desist letter. According to Sabi, Nintendo managed to get in by phone and let Sabi know that the company was aware of their actions. Nintendo followed up with an email from a lawyer which stated that Nintendo would respond with legal action if Sabi leaked any more information concerning the E3 Nintendo Direct.
The reason why Nintendo might have been prompted to take action is that the E3 Nintendo Direct is going to be the last major press event at E3 2019, which means that Nintendo could potentially lose a lot of enthusiasm for its reveals if they are spoiled beforehand. Sabi has already revealed a couple of the announcements from the E3 Nintendo Direct (which we won't share here for those who don't want to be spoiled), but the majority of the conference is still a mystery.
Nintendo has revealed that the next the subject of supposed leaks. It might be hard for leakers to brag about being correct about Super Smash Bros. Ultimate DLC reveals, as they will be too busy being hunted by the ninja-lawyers that Nintendo clearly has on the payroll.