If it is a positive screen printing, that is the model, such as 1A, G1, 2L, etc., which is also for the convenience of marking and writing a simple number, the real model is corresponding to it one by one, you also know that so small audion is impossible to write 2N5551 such a model.
The back mark is generally the manufacturer's mark, which has no practical significance for us.
I don't seem to have seen the one you mentioned, because many integrated circuits are made of triode packages, such as the in-line 18B20, HT7044, 78L05 and so on, including the chip Hall device, these are integrated circuits. The triode-like device of the patch is not a triode. Better to check the model number. If you want the triode patch comparison table, I have three versions, email them to you. I am speechless, you said, the explanation has been explained to you, the information has been sent to you, and you have returned to me hanging in the air, which is a bit of a force not to please, and will resolutely not give a first-class answer in the future