Source: The 451 Group

The last quarter was the single best quarter in history for open source companies raising venture capital according to the 451 Group.

The amount hit $203.75 million, up from $100.4 million year-over-year and after a really nasty downturn in the fourth quarter of ’07.

The previous record of $193.7 million was set in 4Q06.

The Q1 investment went into 20 start-ups, with the average size deal being worth roughly $12 million.

The researcher cautions, however, that most of the money went to established firms like Greenplum and SugarCRM and not into seed rounds or Series A financing and, for what it’s worth, most of the announcements, representing the bulk of the money, were made in January.

The 451 Group figures that despite the good start it will be hard to beat the banner year of 2006 when open source concerns raised $546.3 million. Disclosed funding deals were down almost 41% last year to $323.87 million compared to 2006, according to 451’s tally. Heck, last year was even lower than 2005 when open source companies raised at least $334.82 million.