Variety confirms that the studio has won a heated bidding war for the project, beating out offers from both Fox and Universal.
The film is being envisioned as a big-budget comedy, which Dobkin will direct from his own script.
The acquisition casts doubt on reports that Guy Ritchie was to begin working on a King Arthur adaptation of his own for Warner Bros.
Antoine Fuqua was the last director to release a retelling of the Arthurian legend, in the poorly-received 2004 film King Arthur starring Clive Owen and Keira Knightley.
Dobkin is currently best known for his successful comedy films, including Wedding Crashers, Shanghai Knights and Fred Claus.
Watch the trailer for Dobkin's new film The Change-Up below: