Someone will probably come and correct me, but I'm pretty sure they're not. I've never heard of a need to get MLCCs the correct way around.
The way Wikipedia shows them as being constructed, they're basically entirely symmetrical so it shouldn't be an issue at all.
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Someone will probably come and correct me, but I'm pretty sure they're not. I've never heard of a need to get MLCCs the correct way around.
The way Wikipedia shows them as being constructed, they're basically entirely symmetrical so it shouldn't be an issue at all.