The ChipGuide uses these (collector) definitions of Current and Obsolete:

Current - The chip is in use at the casino, meaning you can get the chip by going to the casino

Obsolete - The chip is no longer in use at the casino, meaning that to get the chip you have to get it from somewhere else, namely trade or buy

The definitions have nothing to do with whether or not you can cash in the chip.
The ChipGuide does not specifically look to maintain current vs. obsolete information.
We mark chips current when they are first released and put on the ChipGuide.
If we find out that they are no longer in use, we will mark them obsolete.
If the casino is closed, they are automatically marked obsolete.