The Boston Athletic Association plans to release official race results and times for all runners on Friday.
In a statement on its website, the group asks for patience as they resolve final results for those who were still on the course when two bombs exploded near the finish line. Three spectators were killed and more than 170 people were injured.
The explosion occurred just over four hours and nine minutes into the race, about 2 ½ hours after the winners crossed the finish line.
BAA leader Tom Grilk has said it is committed to holding the 2014 marathon.