Broberg agreed to terms on an offer sheet with St. Louis on Tuesday for a two-year, $9.16 million deal.
Broberg played in just 12 regular-season contests with the Oilers last year in which he notched two assists, four hits and six shots while averaging 11:37 of ice time. In the minors, the 23-year-old blueliner was significantly more productive with 38 points in 49 outings for AHL Bakersfield. The Oilers will have seven days to match the Blues' offer in order to retain Broberg.