On Monday, DeepSeek released an experimental version of its latest simulated reasoning language model, DeepSeek-V3.2-Exp, which introduces what it calls "DeepSeek Sparse Attention" (DSA). It's the company's implementation of a computational technique likely already used in some of the world's most prominent AI models. (The full extent to which Western AI companies currently use sparse attention in their latest models remains undisclosed.) Despite sparse attention being a known approach for years, DeepSeek claims its version achieves "fine-grained sparse attention for the first time" and has cut API prices by 50 percent to demonstrate the efficiency gains. But to understand more about what makes DeepSeek v3.2 notable, it's useful to refresh yourself on a little AI history.