This nib appears to be a typical Aikin Lambert product, but when turned over a surprise awaits.
US patent 410272, issued to John T. Foster of Arlington, New Jersey. The most relevant passages in the patent description follow:
The sixth step of my process consists in striking the nib portion of the blank by a punch, a single blow being ordinarily sufficient, the punch being formed with a roughened or engraved face to impart a rough or indented or matted surface to the pen . . .
The surface of the nib is roughened, not merely by superficial scratches, as in the stoning process, which in course of time are worn off by rubbing of the pen against a sponge or pen-wiper to clean it, but by indentations deeply and forcibly pressed into the metal, whereby a better capillary surface is afforded for holding the ink.
Foster's other patents have nothing to do with writing instruments, and it appears his interest in nib manufacture came out of an involvement with general metalworking. I have not seen any other nibs made to Foster's design, so it would seem that despite the patent's claim, this stippling offered no measurable benefits -- and one wonders if it might even have interfered with capillary action along the slit.