# How Amazon Optimizes Where to Store Products to Avoid Stockouts > A mathematical method for deciding how many items to stock in different warehouses to minimize the cost of running out of products. - **Patent:** US 8732039 - **Original title:** Allocating regional inventory to reduce out-of-stock costs - **Owner:** Amazon Technologies Inc - **Granted:** 2014 - **Status:** Active - **Times cited:** 41 - **Field:** ecommerce, ai_ml ## What it does This patent describes a computational method for distributing a fixed supply of goods across multiple regional warehouses. It uses a probabilistic model—specifically a gamma distribution—to forecast customer demand in each region. By calculating the specific financial cost of an out-of-stock event in each location, the system determines the optimal number of units to store in each warehouse. The goal is to minimize the total expected cost across the entire network, ensuring that high-demand or high-cost-of-failure regions receive priority in inventory allocation. ## What it does NOT cover - Does not cover real-time inventory replenishment triggered by individual customer purchases. - Does not cover the physical logistics of transporting goods between warehouses. - Does not cover demand forecasting methods that do not utilize a probabilistic distribution model. - Does not cover manual inventory management decisions made without the specified mathematical optimization. ## The clever bit The system treats the 'cost of being out of stock' as a variable that can be balanced across regions using a set of equations, effectively equalizing the marginal risk of stockouts across the entire network. ## Real-world examples 1. Amazon fulfillment center inventory distribution 2. Automated supply chain management software 3. Regional warehouse stock level planning ## Why it matters This technology is fundamental to modern e-commerce, where the speed of delivery is a primary competitive advantage. By mathematically balancing inventory across a vast network, companies like Amazon can reduce shipping costs and avoid the significant financial penalty of failing to fulfill an order from the nearest warehouse. It transformed inventory management from a reactive process into a predictive, data-driven optimization problem. ## Frequently asked questions ### What does How Amazon Optimizes Where to Store Products to Avoid Stockouts cover? A mathematical method for deciding how many items to stock in different warehouses to minimize the cost of running out of products. ### Who owns patent US 8732039? Amazon Technologies Inc owns this patent, granted in 2014. ### When does this patent expire? This patent is expected to expire on May 20, 2034, when the invention enters the public domain. ### What is patent US 8732039 cited by? This patent has been cited by 41 later patents that build on its ideas. ### What problem does this patent solve? This technology is fundamental to modern e-commerce, where the speed of delivery is a primary competitive advantage. By mathematically balancing inventory across a vast network, companies like Amazon can reduce shipping costs and avoid the significant financial penalty of failing to fulfill an order from the nearest warehouse. It transformed inventory management from a reactive process into a predictive, data-driven optimization problem. ### What does this patent NOT cover? Does not cover real-time inventory replenishment triggered by individual customer purchases. **Full plain-English explainer:** https://patentbrief.org/patent/us/8732039/amazon-subscribe-save **Original patent:** https://patents.google.com/patent/US8732039 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Warehouses Plan Pallet Stacks for Incoming Shipments](https://patentbrief.org/patent/us/11767169/warehousing-systems-and-methods) — This patent describes an automated warehouse system that plans how to stack incoming items onto pallets to perfectly fit available storage racks, and automatically sorts out incorrect items. - [How Warehouses Sort Items with Magnetic Levitation Shuttles](https://patentbrief.org/patent/us/12077385/systems-and-methods-for-high-speed-warehouse-order-sortation) — This patent describes a warehouse system that uses magnetic levitation shuttles to quickly sort individual items for customer orders, guided by a control system that directs shuttles based on item type and order needs. - [How Amazon Delivers Content Faster Using Local Servers](https://patentbrief.org/patent/us/9332078/facebook-memories) — Amazon's 2016 patent describes a system for breaking down digital content into smaller pieces and storing them on servers located near users to speed up downloads and reduce network traffic. - [How Robots and Mobile Shelves Fulfill Orders in Warehouses](https://patentbrief.org/patent/us/10947045/warehousing-and-order-fulfillment-systems-and-methods) — Target's patent describes an automated warehouse system where mobile robots bring shelves and shipping containers to a central robot that picks items directly into orders, all without human hands. - [Automated System for Emptying and Sorting Items from Shipping Containers](https://patentbrief.org/patent/us/11648589/systems-and-methods-to-enhance-the-utilization-of-order-sortation-systems) — This patent describes an automated system for quickly emptying items from shipping containers, like totes, by inverting them onto a conveyor belt for scanning and sorting into customer orders.