Is it possible International Master To beat Grandmaster

In tournament game. I do not mean blitz game. I know that Fisher did beat grandmasters before he did aquire grandmaster title, but how special feat that is?

Yes, it is possible. Sometimes even FMs beat GMs. Even if the GMs would win most of their games against an opponent, they will lose some games if the opponent is strong enough.

Happens all the time. That's how IMs become GMs.

Sure, upsets happen all the time.  Just because you get the GM title doesn't make you God almighty.

While I have yet to beat a GM, I have beaten an IM as a lowly Expert.  Upsets happen all the time.  That's why we play the game!

Some IMs are actually stronger than some GMs ... Kramnik was a 2600 FM and skipped the IM title going straight to GM so I imagine he beat many GMs as an FM . 

I have a friend rated 2250 who beat GM Dmitry Gurevich rated 2550 back in '86--it was his second GM scalp.  But he lost a lot of games to other GMs, too.

I have read but not confirmed that Bobby Fischer never lost to an International Master after winning his grandmaster title.  I havn't checked Kasparov or Carlsen but I'd be surprised if either lost a game against an IM at slow time controls.

I don't know about IMs, but Fischer lost to a CM in 1970.

I thought that was an exhibition at fast time controls.

Nope, it was at Rovinj/Zagreb vs. Kovacevic--I think it was the last time Fischer lost as white in a French.

Wasnt the winning player an IM ? 

Has Kasparov or Carlsen ever lost to an IM?

ofcourse. they didnt go from 0 to 2500 in 0 time

You mean after they got their GM titles or before?

Because I feel like they would have had to at some point in their chess careers....

I believe he was a CM at the time, and later made IM, but I could be wrong about that.  I just remember that my friends were wondering how Fischer could have lost to a CM--the only game he lost in the event.

In 76 he was awarded the GM title but I cant find anything on his title or rating when he beat Fischer ... strange .  That was Fischer's only loss and he won the event . Kovacevic finished tied 9-11 , how strong was the field ?  Hard to imagine he was only CM at the time but cant find otherwise ... 

http://www.chessgames.com/perl/chessgame?gid=1044313

Here is the game for those curious .  I bet Fischer was very upset with this loss but he did overpress .... 

what is a cm

I was just going over Fischer-Kovacevic 1970 last week. It's a fun game. As a French player, I take a certain pleasure in Fischer's losses to the French. I can imagine Fischer seething over these defeats to weaker players in an opening variation he considered unsound.

According to Wiki, Kovacevich didn't make GM until 1976. He's an interesting guy in that he mostly played the London System as White. Even co-wrote a book on it.

I'll bet pfren can tell us some Kovacevic stories.

From what I remember about the game is that Fischer was gracious to him and congratulated him on the win--then went on to take it out on everone else.  But remember, guys, that was some time ago, and that we didn't have the Internet, so maybe it was a misprint in the paper, though I do recall us wondering how it could have happened.