Some fountain pen nibs were designed with tips that angle upwards. Waterman offered them as an option from an early date, calling them "turned-up" or "ballpoint" nibs. Older examples bear no special imprint, but many examples from the mid-1920s on are marked "BALLPOINT".
Other companies offered turn-up nibs, including Parker, but they are uncommon. Sheaffer, however, adopted a turned-up profile as standard for their nibs starting in the '30s, making Sheaffer turn-ups by far the most common today. Sheaffer's conical Triumph nibs, introduced in 1942, nearly all display this feature. Turn-up nibs place the iridium tip more nearly parallel to the writing surface, and so are especially suitable for left-handers and others who hold their pens at a steep angle.