Its stated on the Company of Misery's page that the signifigance of their symbol is unknown.
What do you all think it means?
As we can see its an upward arrow, the sign fo Space Marine Tactical Squads engulfed in flames.
Personally I think it symbolizes the destruction of loyalist space marines. Since the Company of Misery seek to, quoting the CoM's page "....show these simple-minded fools [the imperium] that hope is less than worthless" and the loyalist marines are known as the greatest symbol of hope in the Imperium