Lpo vs law firms. is there a major difference in the style of working?

I'm working as a recruiter and have currently been tasked with sourcing litigation profiles for a certain LPO.

In their JD, they have specifically mentioned that they only want candidates from other LPOs. 

My question is,

"Is there a major difference in the working style of Law forms and LPOs. If my client has specifically talked about LPOs and I send him candidates from law firms, would it cause a major difference?"

Thanks