These patches use derby text or imagery to promote a company or business.
Derbyrox was a short-lived derby apparel company. They produced several patches based on different roles in derby as part of a promotional effort. This is the blocker patch.
Derbyrox was a short-lived apparel company who created a series of promotional patches based on various roles in derby. This is the referee patch.
Extreme Skates Roller Derby is a popular Australian skate shop in Brisbane, Queensland.
Extreme Skates Roller Derby is a popular skate shop in Brisbane, Queensland Australia. This design is more commonly found as a sticker, but a shop owner assured me the picture is genuine and it was released in patch form as well.
I haven't been able to find much about this company; I'm not sure it's still in business. I'm also not sure what the skater is holding in their hand. A referee whistle on a lanyard? Something else? I can't tell.