Hello,
To best assess the impact on your client’s situation,I recommend a small “proof of concept” exercise as follows:
Change the maximum length of the Inventory key in a test copy of your tenant.
Once the Inventory Key is expanded to 45 characters, expand a few stock/non-stock item ID’s to take advantage of all the characters.
Test all data entry screens, GI’s, and Reports including all ISV’s and customizations. Test processes like Orders, shipments, transfers, and receipts, imports, and exports. ( Follow your normal testing scripts as if you were preparing for an upgrade.)
If you and your customer are satisfied with the outcome, repeat the segmentation expansion in the live tenant.
Good luck!
Laura
Thanks @Laura02 .
Increasing the field length would need to be done with a customization, wouldn’t it?
Good point!
I had not considered your customer is already at the max size for Item ID’s.
I don’t see any posts related to increasing Inventory ID beyond the limit, but I think the process you will need and impact to consider is very similar to the below post answered by Reza, where expanding GL Account number beyond the natural maximum is discussed:
HTH
Laura
@donnadeskins55 sub-items is not a viable option
Dana makes another good point: sub-items is being deprecated, phased out. Please review the following related post answered by @Dana Moffat :
Laura
@donnadeskins55 also curious about the need for such a lengthy Inventory ID. Is it truly the Inventory ID or is this a composite of other info along with the Inventory ID?
Hi @Dana Moffat, I posed that question to the customer.
I’m very familiar with their processes and I can’t think of a reason they would need the Inventory ID to be that long.
I’ll let you know when I hear back from them 
My customer has determined that they won’t pursue increasing the length beyond 30 characters.
It was something the engineering team was looking for to add more intelligence to the part number.