I don't know which ones are fake. I'm no expert. I'm only saying the ones I have I know are real due to their age, source, and quality. These pics match with what I've seen as authentic. My intent is so you can use them for reference.
I bought a bunch of fake Sanken transistors from a reputable supplier even after I told them how to spot fakes (Chinese writing on the box was a clue). These transistors rated at 17A blew at 1A. I was able to return them. I have a policy at eBay. If it doesn't say it is... it isn't. If they don't say it's NOT scratched... it is scratched. Notice the wording of the eBay ads. Genuine, OEM (meaningless) Panasonic (copies?). Matsushita? I wasn't aware of the trident logo being valid.
The underscoring and size of the code is what caught my attention as POSSIBLY being a way to spot fakes. All the same date code isn't valid for mine as they all came from the same batch.
I bought a bunch of fake Sanken transistors from a reputable supplier even after I told them how to spot fakes (Chinese writing on the box was a clue). These transistors rated at 17A blew at 1A. I was able to return them. I have a policy at eBay. If it doesn't say it is... it isn't. If they don't say it's NOT scratched... it is scratched. Notice the wording of the eBay ads. Genuine, OEM (meaningless) Panasonic (copies?). Matsushita? I wasn't aware of the trident logo being valid.
The underscoring and size of the code is what caught my attention as POSSIBLY being a way to spot fakes. All the same date code isn't valid for mine as they all came from the same batch.