Given that it has a PTPX ID, it's probably a pressed Sony published promo disc of some sort. Not getting any hits on any public DBs for that number, though. So can't really tell you more than that.
I think the disc has some special utilities for tests. I can't check it now. I found these pictures on Yahoo Japan.
Probably from a repair/service center or something then, I presume? By the way, any idea what the T in PTPX stands for? It seems like the second figure is the only thing that changes in Sony IDs like that. (PAPX and PCPX being the ones I seem to recall being the most common)
