Putting chips into a pot after an all in is not normally ambiguous. But doing it when that player still has to make the pot correct from the previous wager makes it ambiguous, as the chips could be going in for two different reasons. Add to this the fact that the dealer didnt not announce call, or showdown, and the responsibility clearly lies with the all in player to protect his hand until the situation is clarified.

Putting chips into the pot that you already owe as a result of a previous bet is ambiguous.

People put out an incorrect number of chips and correct it later all the time. I've never seen this ruled a call of a subsequent bet.

For instance, in limit games, people will frequently throw out a random number of chips in order to bet. If someone in a 20/40 game throws out seven chips on the river, is immediately raised, and then puts out one more chip to correct his bet, I definitely don't think that should be ruled a call of the raise.

The OP's example is more questionable because of the time taken and the amount of chips involved. And the player should realize this and announce his intention. But it is still ambiguous, and both players should protect their hands and their action in this spot.

From Robert's ... I don't think anyone is disputing this but here it is anyway ..

13. A player who bets or calls by releasing chips into the pot is bound by that action and must make the amount of the wager correct. (This also applies right before the showdown when putting chips into the pot causes the opponent to show the winning hand before the full amount needed to call has been put into the pot.) However, if you are unaware that the pot has been raised, you may withdraw that money and reconsider your action, provided that no one else has acted after you. At pot-limit or no-limit betting, if there is a gross misunderstanding concerning the amount of the wager, see Section 14, Rule 8.

This hems in our Mr H. quite a bit ...
1) Added chips to the pot ... even though they 'technically' were already in the pot!
2) Mr H. definitely knew the pot had been raised, no back door there. If he was a cool enough customer to hold back his reaction to seeing the winning hand then tip your hat to him.

I agree that chips could have been added for 'only' fulfilling his bet purposes but Mr H. needs to protect his interest by explaining his actions. He easily could not have made his mind up at that point and was just separating his chips to see what he had behind.

The door for ambiguous is open, but he might have to turn sideways to get through it! GL

RROP also says this about not showing your hand if the amount put in doesnt match the bet. It also even points out that the floor can take the character of the individual into account when determining whether to hold him to a call or not. If player B had just protected his hand instead of showing before anyone said call or showdown, there would be no issue at all.

"12. Because the amount of a wager at big-bet poker has such a wide range, a player who has taken action based on a gross misunderstanding of the amount wagered may receive some protection by the decision-maker. A "call" or “raise” may be ruled not binding if it is obvious that the player grossly misunderstood the amount wagered, provided no damage has been caused by that action. Example: Player A bets $300, player B reraises to $1200, and Player C puts $300 into the pot and says, “call.” It is obvious that player C believes the bet to be only $300 and he should be allowed to withdraw his $300 and reconsider his wager. A bettor should not show down a hand until the amount put into the pot for a call seems reasonably correct, or it is obvious that the caller understands the amount wagered. The decision-maker is allowed considerable discretion in ruling on this type of situation. A possible rule-of-thumb is to disallow any claim of not understanding the amount wagered if the caller has put eighty percent or more of that amount into the pot.
Example: On the end, a player puts a $500 chip into the pot and says softly, “Four hundred.” The opponent puts a $100 chip into the pot and says, “Call.” The bettor immediately shows the hand. The dealer says, “He bet four hundred.” The caller says, “Oh, I thought he bet a hundred.” In this case, the recommended ruling normally is that the bettor had an obligation to not show the hand when the amount put into the pot was obviously short, and the “call” can be retracted. Note that the character of each player can be a factor. (Unfortunately, situations can arise at big-bet poker that are not so clear-cut as this.)"

Seems like an angle

Pay it all

Both players and the dealer all screwed up here. Any of them could have clarified the situation and avoided the problem.
But, by not correcting his bet until after the other guy had acted and gone AI, and then silently putting in more chips while facing an AI bet, Mr. Honorable primarily created the ambiguity, and I would rule against him.
(And I think that the discussion ITT demonstrates that it was ambiguous.)
If deliberate, his actions would have been a classic angle. Maybe just an honest error, but no way to really know.

What did he have? If he had complete air, that goes a long way to show that he didn't mean to call.

This.

If I'm player B after my all in bet, I'm asking player A, as he's moving chips in, if he calls, before showing my hand, because the pot was physically short when I went all in. You have to protect your pot/action before showing because the pot wasn't physically correct.

Frankie518 is the poker manager there at Turning Stone. For some reason he can't get into this thread. Just received a Private Message from him with the following:

Thank you for the info...there are a few things that would need to be addressed in this situation. First the dealer should have not let it get as far as it did without using all-in buttons or completing bets for clarification. For this situation, I would have had Player A be responsible for calling the all-in bet. His forward motion of pushing in with the red stack in both situations acknowledges a call. First red stack called the $280 bet, second red stack called the All-in bet. Now, since we all know there are gray areas in poker, there may be an instance where the reverse call would be made depending on various situations, past history, skill level and/or prior offenses. But in the purest sense of the rules, I would see it as Player A calling the All-in bet. Thanks!

I agree that looks awfully suspicious. Nobody should have let the pot continue that long without getting his $180 in, which takes no time at all. The dealer should have asked him to complete his bet. The all-in raiser shouldn't have spazzed out and announced his hand though since the situation was ambiguous. Blame on both players and the dealer. I'd probably rule it a call simply because he screwed up by not putting chips in quick enough.

The manager clearly didn't get the right story. He says the pushing in of the first red stack called the $280 bet. But that player wasn't calling the $280 bet, he made the $280 bet verbally, and only put out 100 in chips. So the first red stack didnt call anything.

Either that or it was a mistype. Agree that doesn't make sense.

He could have meant first stack made the $280 bet and the second stack called the all in.

Player A's intention may very well have been to complete the $280 bet that he announced and then muck his hand. I'm not saying this is always an angle, but in this case I would make A pay the bet.

If player A has a reputation for being honorable and not an angle-shooter, then it's also fair to say he is experienced enough to know that putting chips in the pot when facing a bet is probably going to be ruled a call. I don't quite understand how someone would risk being forced to call here by putting chips in the pot without explaining his action. If I'm player A, I'm going to loudly announce to the table that I'm just completing my $280 wager and not necessarily calling the all-in yet. By failing to do so, player A did not protect his interest in the pot.

Pay that man his money.

In my casino this would be a call to the all in.. it doesn't take 30 seconds to complete putting your chips over the line for a "$280" bet. Shocking play