The trademark lookup site is such a weird place, some cool stuff I've discovered:
Pac-Man World 3 was originally called "Pac-Man World 3: The Elixir of Life"
This SEGA logo, which they filed for in 2019:
Nintendo filed a trademark for "QUBE" in the 70s. At first I thought it was something to do with the Viacom-owned interactive 70s TV channel QUBE, but seems not judging from the time frame - specifically with the registration coming after the channel
This image of Toon Link, at first I thought it was stolen fan art given the art style doesn't fully match up with any toon-style Zelda games, but it seems like it was drawn for the trademark registration
In the 90s, Viacom filed trademarks for pretty much every character from CatDog (they were super enthusiastic about this show when it came out, but SpongeBob ended up being the big hit) - sorry to anyone with an unrelated idea for characters called "the Greaser Dogs" or "Rancid Rabbit".