Man Killed in His Office

A man got killed in his office. The suspects are Edison, Maxis, Jason, Janna, Sofia, Patrick. A calendar near the man has blood, written 6, 4, 9, 10, 11. Who is the killer?


Jason is the killer.

The numbers represent the starting letter of the month they stand for in a calendar:
6 – June (J)
4 – April (A)
9 – September (S)
10 – October (O)
11 – November (N)