# MPN in Infor LN: Manufacturer Part Numbers, Items and Suppliers > Source: https://netray.co/erp-help/mpn-in-infor-ln-manufacturer-part-number-item-supplier > Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems. > Section: ERP Help ## Short answer Infor LN does not treat the manufacturer part number as a single magic field. You normally hold the MPN through the item code system (alternative codes tied to your own item code) and through supplier-specific item data on the buy-from business partner, so purchase orders can print the supplier or manufacturer number while stock stays under your own item. ## Kind how-to ## System infor-ln ## Erp Infor LN ## Module Common / Item Base Data / Purchase Control ## Query mpn in infor ln ## Alternate Queries - infor ln manufacturer part number - infor ln supplier item code - infor ln item code system - infor ln link manufacturer part to item ## Applies To Infor LN 10.x (Common, Item Base Data and Purchase Control packages). Session codes and field names differ slightly between releases, so confirm them in your own session search. ## Steps ### How to hold and use an MPN in Infor LN **Items:** Decide the rule first: your own item code is the identity, the MPN is an attribute or cross reference. Do not create a new item per manufacturer number unless the parts are genuinely not interchangeable. Open the Items - General data in Item Base Data and confirm the item exists with the correct purchase and warehousing flags. Open the item code system sessions (search the Web UI for Item Code System or Item Codes) and define a code system for manufacturer numbers, then attach the MPN as an alternative code on the item. In Purchase Control, maintain the item data per buy-from business partner so the supplier's own item number and description are stored against your item. Check that your purchase order and request for quotation reports print the supplier item code, not only your internal code. Test with one real item: create a purchase order, confirm the supplier code prints, then search by the MPN in the Web UI to confirm you can find the item from it. ## Sections ### Why LN has no single MPN field **Body:** LN is built around one internal item code per stocked thing, and external identifiers hang off it. The same item may have a customer number, a supplier number and a manufacturer number. Each lives in a cross reference rather than in the item master itself, which keeps stock, costing and planning on one record. The consequence is that the MPN is rarely on the item screen. If you need it on a screen, a report or in a search box, you have to design where it is stored and who maintains it. That design decision matters more than the clicks. ### Choosing between item code system and supplier item data **Body:** Use the item code system when the MPN is the same regardless of who you buy from, for example a catalogue number from one manufacturer. This lets any user find the item by typing the MPN. Use supplier-specific item data when the number depends on the distributor, because a distributor may reprint a manufacturer number as its own stock code. Many electronics and machinery buyers need both: the manufacturer number for engineering and approved manufacturer control, and the distributor number for ordering. If approved manufacturer lists matter for quality or defense work, keep that in a controlled structure owned by engineering, and use the LN cross reference only as the lookup. ### Cleaning up MPNs that are already messy **Body:** Most sites inherit MPNs typed into item descriptions or in free text. Export the item descriptions, separate the number from the text, and load them as alternative codes in a controlled import. Run duplicate checks first: the same MPN on two internal items is a real data problem, not a formatting one. Keep the manufacturer name next to the number. Two manufacturers can legitimately use the same string. **Code:** -- Concept: find the same MPN pointing at more than one item -- (run on a copy or via a read-only reporting view; table and field names depend on your release) SELECT mpn, COUNT(DISTINCT item) FROM item_cross_reference GROUP BY mpn HAVING COUNT(DISTINCT item) > 1; ## Pitfalls - Creating a separate LN item for every manufacturer number, which splits stock and breaks MRP. - Storing the MPN only in the item description, which is not searchable as a code. - Forgetting to add the manufacturer name beside the number, so two vendors with the same string collide. - Assuming reports will print the supplier code without changing the report layout. ## Ai Angle An AI assistant grounded in the LN item and purchase data can answer which item an MPN maps to, flag the same MPN on two items, and draft the cleanup list for a data steward. ERPray runs read-only over LN data and shows the query it used, so the buyer or engineer can check it. Any bulk change to cross references should still go through your normal approval and import process. ## Faq ### Is there a standard manufacturer part number field on the LN item? **Answer:** Not as a single universal field in most setups. LN usually holds the MPN through the item code system or supplier item data. Check your release in the item and purchase sessions, because customization and newer versions can add fields. ### Should every manufacturer number be a separate item? **Answer:** No, only when the parts are not interchangeable. If they are form, fit and function equivalents, keep one item and record the manufacturer numbers as alternatives so stock and planning stay combined. ### Can I search LN by MPN? **Answer:** Yes if the MPN is stored as an alternative item code, because you can then find the item from that code. If it lives only in a description you are limited to text search in reports or an external query. ### How do I get the supplier item number on the purchase order? **Answer:** Maintain it in the supplier-specific item data and make sure the purchase order report layout includes that field. If it still does not print, the report is the next place to look. ## Search terms mpn in infor ln, infor ln manufacturer part number, infor ln item code system, infor ln supplier item, infor ln alternative item code, infor ln purchase item data, infor ln approved manufacturer, infor ln item cross reference --- Talk to an engineer: https://netray.co/contact?intent=erp_ai | Machine catalog: https://netray.co/agent/catalog.json