This means AlphaGo won the match with two games left to play.
Charities will benefit from the $1,000,000 prize.
Some more detailed commentary and pictures will be available on the GoGameGuru website.
Detailed game records and updates about the match can be seen here.
In the Google DeepMind Challenge Match, being held in Seoul from 9th-15th March, Lee Sedol lost the second game in the match, having been outclassed in some middle-game play in the centre.
Lee (playing White) was in his final period of byo-yomi after the two-hour main time, whereas AlphaGo (Black) was in its first.
The final score was a few points in Black's favour, so Lee resigned, as in the first game.
Lee Sedol: "Yesterday I was surprised by AlphaGo’s play, but today I’m quite speechless. At no time did I feel that I was leading, and I thought that AlphaGo played a near-perfect game." When asked what were AlphaGo’s weaknesses “Obviously I haven’t managed to find them out…” and when asked about his prediction for the third game said “It’s not going to be all that easy for me, but I’m going to exert my best efforts to win at least one game..
Whilst the world was holding its breath waiting for the start of the Google DeepMind Challenge in Seoul there were some more prosaic games of Go being played - the latest round of the Pandanet European Go Team Championship.
The UK has got off to a poor start in the second division, but with our latest 3-1 win over second-placed Slovakia we're gradually hauling ourselves up the table.
Andrew Simons was our sole loss, not totally unexpectedly to to 1 dan pro Pavol Lisy, but our other three (Bruno Poltronieri, Alex Kent and Charlie Hibbert) all scored good wins to round off the match.
Andrew Simons said: "My game was rather like my first game of the British Championship, a disappointing loss after throwing away a large opening lead in late fighting, though I suppose I should be glad to have outplayed Pavol in the first 100+ moves.
In the Google DeepMind Challenge Match being held in Seoul from 9th-15th March Lee Sedol resigned after the 186th move, when he realised that he was about 7 points behind and without hope of winning.
Congratulations to the DeepMind team, although some of the non-UK members may not be so happy about the GB flag being shown for AlphaGo (Lee obviously has a Korean flag).
Aja Huang, 5 dan, was their representative playing the moves on the board against Lee, who had Black.
“#AlphaGo WINS!!!! We landed it on the moon,” tweeted DeepMind CEO Demis Hassabis after the game. “So proud of the team!! Respect to the amazing Lee Sedol too.” At a jam-packed post-game press conference, Lee admitted “I was so surprised. Actually, I never imagined that I would lose.
The AlphaGo v Lee Sedol match is now less than 24 hours away. Are you ready? Will you be getting up early? What are you planning for the weekend? Watch our status page here.
At the Press Conference in Seoul this morning, Alphabet (parent company of Google) executive chairman Eric Schmidt said “The winner here, no matter who wins, is humanity”.
Lee Sedol seemed very confident from the various Korean news items, although he's backtracked a little at this Press Conference, being quoted by the BBC as saying "Playing against a machine is very different from an actual human opponent. Normally, you can sense your opponent’s breathing, their energy. And lots of times you make decisions which are dependent on the physical reactions of the person you’re playing against.
On Saturday 30 children from six schools in South Manchester attended a Go workshop at Greenbank school. Martin Harvey had used his connection with Cheadle Hulme School to contact the local Educational 'Gifted and Talented' scheme, who then sponsored the day and selected the children. Martin and Helen Harvey and Roger Huyshe were kept busy throughout.
While the children were just from years 3 and 4 (and 1 Y5), their attention was good, they learned the basics in the morning starting with Capture Go but progressing immediately to territory Go. In the afternoon they submitted to a hectic 5-round McMahon before parents came to collect them.
The matches will be held at the Four Seasons Hotel, Seoul, starting at 1pm local time (4am GMT) on the following days:
The games will be even (no handicap), with $1 million in prize money for the winner. If AlphaGo wins, the prize money will be donated to UNICEF, STEM and Go charities. The matches will be played under Chinese rules with a komi of 7.5 (the compensation points the player who goes second receives at the end of the match). Each player will receive two hours per match with three x 60 seconds byoyomi.
The delayed deciding third game of the 2015 British Championship was played on Sunday 14th February 2016 at Andrew Kay's mother's house (who provided curry at lunchtime).
Up to 100 fans watched the live relay on KGS in the British room by "BGAadmin" from 10:00.
After 299 moves it was found that Andrew Simons, playing black, was 15.5 ahead.
Andrew Simons is therefore the champion for the first time.
Lucas Baker (2d London), shown on the left left playing Baron Allday, won all his games to win the Cheshire Tournament. The event was held as normal at the Community Centre in Frodsham and alongside the Frodsham Chess Congress.
Others of the 30 players also winning all three games were three of the large team from Cheadle Hulme School: Daniel Atkinson (26k), Jack Nolan (18k) and Jason Brown (16k). In addition the runner-up, Tony Atkins (1k Reading), received a prize and Joel Barrett (20k Manchester) was awarded a prize for winning two games and being told the wrong handicap in his other.
Winners in the self-paired 13x13 side event were youth players Yusuf Ahmed for 12/19, Daniel Atkinson for 9/11 and Matthew Benton for 7/9.
British Go Journal 174, including the full report on the AlphaGo v Fan Hui match is now available online to members at http://www.britgo.org/bgj/bgj174
We're still getting additional media coverage of this match - see http://www.britgo.org/history/media for the latest.