Names Hasbro never lost thanks to (more or less) continuous use
- Optimus Prime
- Grimlock
- Megatron
- Soundwave
- Starscream
- Prowl
- Snarl
- -
Names Hasbro never lost because the US Patent and Trademark Office had forgotten to cancel them
- Defensor
- Galvatron
- Menasor
- Metroplex
- Omega Supreme
- Rodimus Prime
- Silverbolt
- Sky Lynx
- Superion
- Predaking
- Ultra Magnus
- Wreck-Gar
- -
Names Hasbro managed to get back with ease because no-one had tried to take them away in the meantime
- Air Raid
- Astrotrain
- Barricade
- Beachcomber
- Blackout
- Bludgeon
- Blurr
- Bonecrusher - Bone Crusher
- Broadside
- Bruticus
- Buzzsaw
- Cliffjumper
- Cyclonus
- Dead End
- Dirge
- Divebomb
- Downshift
- Dreadwind
- Dreadwing
- Fireflight
- First Aid
- Fortress Maximus
- Hot Spot
- Inferno
- Hoist
- Huffer
- Ironhide - Energon Ironhide
- Jetfire
- Kickback
- Knockout - Knock Out
- Landfill
- Landmine
- Laserbeak
- Long Haul
- Mirage - Mirage GT
- Nightbeat - Nightbeat 7
- Nightstick
- Overbite
- Overload
- Override
- Perceptor
- Ramjet
- Rampage
- Ransack
- Razorclaw
- Red Alert
- Repugnus
- Ricochet
- Roadblock
- Roadhandler
- Rollbar
- Runamuck
- Seaspray - Sea Spray
- Scavenger
- Scorponok
- Scourge
- Sixshot - Six Shot
- Skydive
- Skyfall
- Skywarp
- Sludge
- Slugslinger
- Smokescreen
- Springer
- Storm Cloud - Stormcloud
- Streetwise
- Sunstreaker
- Swerve
- Swindle
- Thrust
- Thundercracker
- Thunderwing
- Tread Bolt - Treadbolt
- Treadshot
- Trypticon
- Weirdwolf
- Wheeljack
- Wideload
- Windcharger
- -
Names Hasbro eventually managed to get back after someone else had claimed them
- Bumblebee
- Ravage - Battle Ravage, Command Ravage
- Shockwave - Shockblast
- Sideswipe - Side Swipe
- Swoop
- -
Names Hasbro had to modify because they're too common these days
- Brawl - Deceticon Brawl
- Brawn - X-Brawn
- Breakdown - Brakedown
- Camshaft - Autobot Camshaft
- Devastator - Constructicon Devastator
- Frenzy - Deceticon Frenzy
- Grapple - Autobot Grapple, Roadblock
- Groove - Autobot Groove
- Hound - Autobot Hound
- Jazz - Autobot Jazz, Meister
- Ratchet - Autobot Ratchet
- Rumble - Decepticon Rumble, Scrapmetal
- Scattershot - Scattorshot
- Scrapper - Decepticon Scrapper, Buckethead
- Skids - Autobot Skids, Skid-Z
- Tracks - Autobot Tracks
- Whirl - Autobot Whirl
- -
Names Hasbro had to find a substitute for because someone else had claimed them in the meantime, or holds a "confusingly similar" trademark
- Bluestreak - Silverstreak
- HiQ
- Hook - Hightower
- Hot Rod - Rodimus Major, Rodimus, Hot Shot
- Mixmaster - Quickmix
- Motormaster - Menasor
- Outback - Fallback
- Overdrive - Windcharger
- Powerglide - Fireflight
- Runabout - Runamuck
- Slingshot - Ro-tor, Storm Jet
- Shrapnel - Insecticon
- Trailbreaker - Overhaul, Autobot Ratchet, Ironhide, Swindle
- -
External Link
- [Transformers trademarks and their current status with Hasbro http://www.tfarchive.com/toys/trademarks/g1_trademarks_intro.php]