Jay Z -- I'm Waayyy Too Busy for Your Stupid Lawsuit

Jay Z's the hardest working man in show biz ... so claim his lawyers, who say the rapper has such a "grueling" work schedule he can't possibly make time for what they say is a ridiculous lawsuit.

A guy who sued Jay over his Roc-A-Fella logo wants the mogul to sit for a deposition next month. The man says he designed the art back in 1995 and now wants $7 mil for his creation.

Jay's lawyers say in legal docs the depo is trivial and way less important than all the other things he's got going on. The attorneys describe their client as "one of the most prolific and hardest-working businessmen and recording artists in the world."

The lawyers say Jay's 18-city North American tour with Beyonce must take priority over a stupid lawsuit, adding "preparing a stadium tour is a non-stop effort."