Carl Ruben (born 4 August 1903, date of death unknown) was a Danish chess

Chess

Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

 master.

He won a match against Johannes Pedersen (1.5–0.5) at Aalborg 1927, tied for 2nd-3rd in Danish Championship

Danish Chess Championship

The Danish Chess Championship was organised by the Danish Chess Union and first held in 1910. A masterclass was first introduced in 1915. But it is only from 1922 that the title of Danish chess champion was introduced, this was the first year also players from Copenhagen joined.-History:In 1949...

 at Vordingborg 1927 (Erik Andersen won), shared 2nd at Copenhagen 1927 (Politiken, Géza Maróczy

Géza Maróczy

Géza Maróczy was a leading Hungarian chess Grandmaster, one of the best players in the world in his time. He was also a practicing engineer.-Early career:...

 won),
tied for 5-6th at Copenhagen 1928 (Aron Nimzowitsch

Aron Nimzowitsch

Aron Nimzowitsch was a Russian-born Danish unofficial chess grandmaster and a very influential chess writer...

 won), tied for 7-9th at Svendborg 1930 (DEN-ch, Andersen won), and won a simultan game against Alexander Alekhine

Alexander Alekhine

Alexander Alexandrovich Alekhine was the fourth World Chess Champion. He is often considered one of the greatest chess players ever.By the age of twenty-two, he was already among the strongest chess players in the world. During the 1920s, he won most of the tournaments in which he played...

 at Copenhagen 1930.

Ruben played four times for Denmark in Chess Olympiads in 1927, 1928, 1930, 1931, and won team silver medal at London 1927.