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Hi to everyone,I'm conducting an investigation on counterfit STM32F103C8T6 ICs. I'm not affiliated with ST or anything, this is just something i'm doing out of curiosity, to publish the result for the community.Originally the price of the so called "bluepill" STM32 board on AliExpress caught my attention. It is sold for about $1.70, while i didn't manage to find any legittimate distributor selling the chip itself for less than $2.60 ( Octopart ). There are some chinese unauthorized distributors selling it for lower but that's exactly my focus.The other suspicious thing is that, on my bluepill board, i have 128k of flash, while the STM32F103C8T6, from the datasheet, only has 64k. ST is also making a "CBT6" variant that has 128k of memory, but this is not the one that's mounted on the bluepill.I've also discovered that there is a chinese company, GigaDevice, making "compatible" STM32 chips. They have their GD32F103C8T6 compatible, which is sold on Alibaba for about $1.01 in quantity.So i went ahead and bought a chip each, from both ST (sourced from RS-online) and from giga device (sourced from aliexpress), both in the C8 and CB variants.The plan is to dissolve the package and compare the dies under an optica microscopel and, if necessary, on a scanning electron microscope (i have access to one, why not!).Also xraying them would be intresting to see the bonding wires configuration, but for now i don't have access to an xray machine.I took some macros of the various chip to compare them againts the bluepill (see attached image, full resolution here The giga device's package looks quite different in shape, but with a similar texture.The ST's package is similar for the shape but has a much smoother surface.And this is the point where i noticed that one of my genuine chips is from a production plant in China (the C8 version) and has a greater surface marking, the other one is from Malaysia and has a not so good marking. Not bad as the bluepill one, but not as good as the CB version. The bluepill obviously has the worst marking of all five, and it's marked also from Malaysia. The genuine CB has the F on the same line as STM32, while the C8 and the bluepill chips have it on a new line.I've also noticed that on the bluepill chip the pin 1 marker dot is engraved over a dot that's already in the mold. That's strange.Now i'm asking myself if a genuine C8 version made in Malaysia exist and if it has the etched dot, the F on the new line or if the engraving quality is so badSo here's where i need your help: if you have an STM32F103C8T6 from Malaysia or from anywhere else, genuine or not (but please specify), can you post a picture of it?