Career
He was drafted by the Saint Louis Blues in the second round, 49th overall, of the 2004 National Hockey League Entry Draft, and has also spent time in the National Hockey League with the Boston Bruins. Söderberg was selected by the Saint Louis Blues in the second round, 49th overall, of the 2004 National Hockey League Entry Draft. On 23 July 2007, Söderberg was traded to the Boston Bruins in exchange for Hannu Toivonen.
The Boston Bruins signed Söderberg to a three-year, one-way contract through the 2014-2015 season on 13 April 2013.
On 25 June 2015, just prior to becoming an unrestricted free agent on 1 July, Söderberg was traded by the Bruins to the Colorado Avalanche in exchange for Boston"s own sixth-round pick in the 2016 National Hockey League Entry Draft previously traded to Colorado. The next day, on 26 June, he subsequently signed a five-year, $23.75 million contract with the Avalanche, which includes a full no-trade clause for the first two years and a limited no-trade afterward.
Swedish national team controversy
On 9 April 2013, Söderberg reached a multi-year agreement with the Boston Bruins and secured his release from his Swedish team, the Malmö Redhawks. On 11 April 2013, however, the Swedish Ice Hockey Association (SIHF) blocked the release of Söderberg to the National Hockey League in an attempt to secure his position on the Swedish national team for the upcoming International Ice Hockey Federation (IIHF) Ice Hockey World Championships being co-hosted by the country.
In the following days, Söderberg refused to play for Sweden.