From Lexicanum

Chapter Summary

Marine	Basic Data	Chapter Symbol Miniature
	Name: Space Sharks Founding chapter: Unknown Founding: Second Founding Chapter Master: Unknown Homeworld: Unknown Fortress-Monastery: Unknown Main colours: Grey with red markings[1] Specialty: Drop Pod Assaults Battle Cry: unknown Estimated strength: ~1000

Basic Info

The Space Sharks Space Marine chapter took part in the Badab War against the rebel chapters.

After the defeat of the rebellion, they were given the homeworld of the rebellious Mantis Warriors.^[1][1]

In the war, the Space Sharks used their longstanding tactic of Drop Pod assaults in their attacks on the hives of Badab. The large number of dreadnoughts, and their full reserve of Terminator Armour were used to help the Star Phantoms' sieges of the rebellious Chapters. The Space Sharks still to this day carry a long standing grudge and distrust of the Mantis Warriors and the Lamenters.^[1]

The Space Sharks Chapter wears gray armor with a red helmet stripe.^[1][1]

Sources