Family representative Todd Wilson tells TMZ the lawsuit is absurd as the sisters had nothing to do with the creation of the shirts. Kendall and Kylie gave their approval for the design but rely on their brand to handle the rest. Essentially, Wilson tells us, "it's like suing an actor for being in a movie."

Kylie and Kendall Jenner have been slapped with a lawsuit for straight-up jacking Tupac Shakur pics and trying to profit off the work ... so claims the famed photographer in a new suit.

Renowned photographer Michael Miller -- whose portfolio includes Eazy-E, Angelina Jolie and Jack Nicholson -- says he never gave the sisters permission to use his pics, much less to sell them on their website. The shirts have since been taken down, but that's clearly not good enough for him.

In docs, obtained by TMZ, Michael says he never wanted to work with the Jenners, especially Kendall following her PR disasters (We're guessing he's talkin' Pepsi).

As we reported ... the Notorious B.I.G. estate threatened to sue the sisters if they didn't take down the shirts. The sisters did and apologized, but Michael's not budging. He's suing for any profits they made off the shirts.

We've reached out to Kylie and Kendall, so far no word back.