Pic10F202 Master clear will not turn off.

[Archangel]

Is there any chance GPIO.3 is shorted to VDD ? Just asking because you did not mention if this is a PDIP or SMT package, in chk or not . . .

[Elusiveinc]

avioncis,
I did see page 35 and does not give memory location for some reason where the register 9-1 is at. Which I find weird. But there has to be one because the bits are writable says datasheet. But yes at this point it's not looking good.

Arch,
Sorry this is a DIP 8 pin package. vdd seems to be holding it high internally. as there is 5 volt on GPIO.3 with nothing connected. But I'm sure that is the way it is suppose to be. So it doesn't reset itself if someone didn't know they need a pull up resistor. And per data sheet if voltage greater than Vdd will enter programming mode. If you are saying that vdd is being applied externally accidentally no.

[Archangel]

Ok sometimes finding out what it is is by eliminating everything else. So what does your volt meter tell you if you turn ON MCLRE ? Also do you have another chip?edit: (Almost)/edit Lastly are you SURE it is a Genuine PIC? I know it seems silly to entertain the idea of cloning a $0.38 chip but when you are selling 50 million of them . . .
Data sheet says GPIO.3 is connected to VDD when MCLRE is off, I am trying to get my head around how it can serve as an input while connected to vdd unless it's via a WPU, . . . . How "ROBUST" is your power supply? Does grounding GPIO.3 cause the chip to BROWNOUT ? Also check your breadboard for corrosion causing weak connections, seen that many times.