Banks and insurers often top the list of clients exerting the most pressure on law firm billing, but recent data shows financial services shops let that cost consciousness slip in recent months.

Legal departments of companies operating in the financial sector can control rate increases and rein in outside legal spend if they have options and are working with multiple firms, Nathan Cemenska, director of legal operations and industry insights at Wolters Kluwer ELM Solutions, said.

"You're really only as strong as your options. And if you don't have any other options, or maybe theoretically, you have options, but you've never done anything to explore them and know for sure what they look like, then that does not put you in a very good position for negotiations.