In S2E22 of Fringe, "Over There, Part 1", Walter Bishop, Sally Clark, Nick Lane, and Olivia Dunham travel to the Redverse. Its Fringe Division chase and surround them on a bridge, where Lincoln seems to recognize Nick and asks
Nick?
But even though I've seen the whole show (except for the final episodes), it is never revealed how they knew each other, it's fair to say that there's probably a Nick Lane on the Redverse as well, but it's never disclosed how Redverse's Lincoln Lee and Nick Lane knew each other, or is it?