Johnson & Johnson’s (NYSE:JNJ) one of the largest drugmakers in the world, and according to a lawsuit Pfizer (NYSE:PFE) has filed, it’s leveraging its size to negotiate contracts that prevent insurers from paying for cheaper biosimilars to Remicade, its best-selling drug. Pfizer’s suit reveals the lengths to which drugmakers are going to keep sales flowing in from drugs even after patents expire, so let’s take a closer look to see what’s at stake.