Ok, so the chip isn't hidden. You simply never saw it. JFC everything is made so difficult in this forum by all the bull**** literal nonsense. It's getting hard to continue posting here.

That still applies to any number of any color of chips! It only supports "purple doesn't play" as an end-all argument if any other color chip I never saw also doesn't play.

FWIW, I asked a floor last night how he would handle that situation and he laughed and said he’s happy that spot couldn’t really come up for him because their 2/5 game is capped at $500 buy-in. He told me they don’t have a written rule addressing which chips play in which game but dealers are required to check stacks and color down black chips in the 1/2 game. If he would be called to that game because the dealer didn’t notice a non-hidden black chip, he would rule it in play in accordance with how gaming regulations address legal casino chips in table stake games.

[I have no idea if the gaming regulations part is true or not]

All depends on if it is in the rules they have approved by the state gaming commission or not. Some rooms may just say we don't want bigger denom chips in the game so they try to check down any they see and other rooms may actually have it in their ruleset. The ruling would, and should, be very different between those rooms.

We would rule it the same way in my casino. A chip that isn't allowed in the game "doesn't play" but it does not change the size of the players stack. If it is discovered during a hand, the value of the chip is still in play and will be chipped down after the hand.

Wow that is dumb. If it doesn't play, it does NOT play. But your procedure says it does play for one hand. So what's to stop someone from buying in every time with a chip that doesn't play if he knows it plays when caught and he will just change it out after the hand. And why should a chip that doesn't play be allowed to play if the chip is hidden as it was in the OP? Even if the chip is not hidden, his stack looks a lot smaller than if he has the proper chips. Someone on the other side of the table might easily think he playing against a $205 stack instead of the $705 (or whatever) stack that it really is. The only only to stop this is to follow the rule. The chip does not play in any form.

I hope you aren't a dealer or floorman.

So we are making a clear distinction between a Player sitting down or adding on beyond the table stakes with chips that do play and a chip that is 'not allowed' on the table at all, yes?

There are numerous threads where it was determined that a Player's stack at the start of the hand was allowed to remain in play during the hand and then possibly modified after the hand depending on the result.

I like the distinction ... It's no different IMO than a Player using a chip from another casino as a card protector, which I've seen plenty of ... they don't play! GL

Yes, adding chips above the legal amount is a separate issue handled by separate rules.

I think the current confusion is what JD means by “discovered”. As in “previously unknown to anyone”?