Y Combinator is now running four batches per year: Winter, Spring, Summer and Fall. We completed the first ever fall batch last year, F24, and are proud to announce the first ever spring batch, which we are abbreviating as X25. Apply To X25 One of the first questions people ask when we say we are doing a spring batch is what letter we will use to refer to it since “S” is already taken for the summer batch. We considered something like “Sp” or “P” but one founder made the suggestion of using “X” ...