Complex sentence: On May 12,2009, the CSL announced that it had received conditional approval for membership with the CSA as Canada's national professional league, the only league to receive this endorsement from the CSA in 16 years.
Split into simpler sentences: On May 12,2009, the CSL announced that it had received conditional approval to be in membership with the CSA as Canada's national professional league. This the first league to receive this endorsement from the CSA in 16 years.