Following the trademark registered for The Legend of Zelda: Phantom Hourglass by Nintendo in Australia, trademarks for other games from the Zelda series have also been registered.
At the moment, three new games have been registered which are: Ocarina of Time, The Wind Waker, and Skyward Sword.
It's possible that they may be related to the 35th anniversary celebration of the series. It's rumored that a remaster pack will be released for the Nintendo Switch, just like what happened with Super Mario 3D All-Stars for the 35th anniversary of the Super Mario series.
The Legend of Zelda: Ocarina of Time, the fifth installment in The Legend of Zelda series, is an action-adventure game developed and published by Nintendo. The game was released in November 1998 for the Nintendo 64.
The Legend of Zelda: The Wind Waker, the tenth installment in The Legend of Zelda series, is an action-adventure game developed and published by Nintendo. The game was released for the Nintendo GameCube in December 2002 in Japan, in March 2003 in North America, and in May 2003 in Europe.
The Legend Of Zelda: Skyward Sword, the sixteenth installment in The Legend of Zelda series, is an action-adventure game developed and published by Nintendo. The game was released in November 2011 for the Nintendo Wii.