would PGN need updates following recent rule changes?

[gbtami]

I think you are stuck into terminology rather than the intent of the PGN standard.

Even if you want to be pedantic about the details, you are still wrong because the current FIDE laws of chess say:

3.10.2 A move is illegal when it fails to meet the relevant requirements of Articles 3.1 – 3.9

and

A.4.2 If the arbiter observes an action taken under Article 7.5.1, 7.5.2, 7.5.3 or 7.5.4, he shall act according to Article 7.5.5, provided the opponent has not made his next move. If the arbiter does not intervene, the opponent is entitled to claim, provided the opponent has not made his next move. If the opponent does not claim and the arbiter does not intervene, the illegal move shall stand and the game shall continue. Once the opponent has made his next move, an illegal move cannot be corrected unless this is agreed by the players without intervention of the arbiter.

An illegal move is allowed to stay under those conditions, but it's still illegal.

Also, the PGN standard does not define the term "legal move" but from the disambiguation paragraph it's safe to assume the same definition of legal move as within the FIDE rules is used.

Beyond pedantic, what still needs to be addressed is whether the current PGN standard can be used to represent "illegal moves allowed to stay" or some amendment is required.

I still haven't seen the notation for "Black moves the pawn from f7 to g4, while knocking the Black Queen on h4 off the board and moving the White Knight from g3 to g2": in a blitz game it's not such an unlikely situation and many White player would rather continue the game than to claim a time penalty.

Because both under old A4.2 both under new A4.2 "illegal move shall stand" can happen, this is not a new problem at all. Games with illegal moves was played in the past and will be played in the future. If you want to be PGN standard compliant you have only one choice. If the move was illegal because of 3.1-3.9 you can record the remaining game only in a comment. It is not restricted in any way, so you can put a new FEN if you like, or just use words to describe what happened. SAN moves inside {} shoudn't be interpreted in any way by any GUI, because it is just a human comment! Of course you can use SAN in comment but it's not have to be valid moves. All in all I see no reason to change anything in PGN standard because of 2018 FIDE change.

[casaschi]

Because both under old A4.2 both under new A4.2 "illegal move shall stand" can happen, this is not a new problem at all.

Until now "illegal move shall stand" only occurred as a mistake with disregard of the games rules.
With the new FIDE rules, "illegal move shall stand" can happen by a conscious decision of a player in full compliance with the rules.

This seems a major difference to me; if FIDE explicitly allows for this event to happen then it's legitimate to ask the question whether the event should be coded and recorded accordingly in the chess notation.

[casaschi]

I understand your frustration, but for most of us who use this forum, your question is irrelevant.

I accept that, but then why not leaving this thread alone instead of discussing something completely different?

[MikeB]

I understand your frustration, but for most of us who use this forum, your question is irrelevant.

I accept that, but then why not leaving this thread alone instead of discussing something completely different?

Chill , there was no deliberate attempt to hi-jack the thread - people post about they want to post - on any post there are always opportunities to segue to a slightly different topic - it is how a forum works. Get used to it.

[casaschi]

I understand your frustration, but for most of us who use this forum, your question is irrelevant.

I accept that, but then why not leaving this thread alone instead of discussing something completely different?

Chill , there was no deliberate attempt to hi-jack the thread - people post about they want to post - on any post there are always opportunities to segue to a slightly different topic - it is how a forum works. Get used to it.

Sure, that's how it works, no problem; it was just me thinking aloud and wondering once again why people would spend time posting in a thread irrelevant to them. Go figure, human nature I guess...

[gbtami]

Because both under old A4.2 both under new A4.2 "illegal move shall stand" can happen, this is not a new problem at all.

Until now "illegal move shall stand" only occurred as a mistake with disregard of the games rules.
With the new FIDE rules, "illegal move shall stand" can happen by a conscious decision of a player in full compliance with the rules.

This seems a major difference to me; if FIDE explicitly allows for this event to happen then it's legitimate to ask the question whether the event should be coded and recorded accordingly in the chess notation.

Why do you think it is important to know that an invalid move was made by accident or by conscious decision. From recorder point of view this is irrelevant. It happened before 2018.01.01 and will happen after 2018.01.01 also. If the position after the illegal move is illegal you can record the remaining game as comment inside {}. Nothing have to be changed in PGN spec. IMO.

[casaschi]

Why do you think it is important to know that an invalid move was made by accident or by conscious decision. From recorder point of view this is irrelevant. It happened before 2018.01.01 and will happen after 2018.01.01 also. If the position after the illegal move is illegal you can record the remaining game as comment inside {}. Nothing have to be changed in PGN spec. IMO.

FIDE now seem to suggest that a certain sequence of event is now within the rules and a player might have to choose between claiming a move or continuing the game. There might be a value in documenting what happened, in the same way as we like to record legal games for analysis and reference. There might be a value in making sure the PGN standard reflects whatever FIDE tells us might happen during the game. There might be a value in being able to easily browse and analyze such a game, understanding the player decision and the rest of the game. Anyone that has ever remotely worked in something to do with data entry and information storage/processing will tell you that dumping information into free-form text comments is a BAD idea.

What triggered the question in the first place, if you care reading the initial post, was that this remote occurrence somehow happened already in one of the first tournament applying the new rules: nothing less than a game from the current world champion in a world championship tournament. Don't you think it's worth asking whether it should be possible to properly document the Carlesn/Inarkiev game had Inarkiev decided to continue after Carlsen moved out of check with his last move?

Your answer is legitimate, if nothing else because I believe FIDE will likely reverse their decision, but asking the question seems also legitimate.

[carldaman]

Your answer is legitimate, if nothing else because I believe FIDE will likely reverse their decision, but asking the question seems also legitimate.

I hope they'll reverse it, because it's a terrible rule change.

[Ovyron]

Your answer is legitimate, if nothing else because I believe FIDE will likely reverse their decision, but asking the question seems also legitimate.

I hope they'll reverse it, because it's a terrible rule change.

We truly live in interesting times, if they don't reverse it, it could be the end of chess as we know it.

[carldaman]

Your answer is legitimate, if nothing else because I believe FIDE will likely reverse their decision, but asking the question seems also legitimate.

I hope they'll reverse it, because it's a terrible rule change.

We truly live in interesting times, if they don't reverse it, it could be the end of chess as we know it.

My understanding is that illegal moves are still considered illegal, and can be penalized, but only if a claim is made before other moves are made, otherwise the illegality 'stands'. A potential problem is that it may encourage such illegal moves in losing positions, with the hope that the opponent may not notice it.