When a supplier replaces an item, you often still have usable inventory on the old item — while demand and replenishment have moved to the new one. Stock Inheritance (also called supersedure) lets the replacement item count that leftover stock in planning and purchasing, so Recurrency does not recommend buying more until the old stock is used up.
💡 Tip: Stock Inheritance is about supply (on-hand inventory). Item Usage Inheritance is about demand (historical usage). They are separate. You can use one, both, or neither.
Why it matters
Without stock inheritance, Recurrency treats each item’s inventory separately — even when the old and new items are the same product in practice. That can cause:
Over-purchasing on the new item while usable stock sits on the old one
Misaligned planning — demand rolls forward, but supply does not
Manual workarounds to reconcile stock during item transitions
With stock inheritance set up, planning and purchasing use an effective net stock that includes inventory from the replaced items you attach.
How it works
Think of it as a simple family relationship:
The replacement item (the one you replenish going forward) is the descendant
The replaced items (older versions with leftover stock) are the ancestors
When you attach one or more ancestors to a descendant:
The descendant’s effective net stock = its own net stock + the ancestors’ net stock at the same location
Ancestors do not generate their own replenishment against that stock (so it is not double-counted)
Your underlying inventory records in Recurrency and your ERP stay unchanged — only how planning and purchasing use the stock changes
In plain terms: Stock from these replaced items is included in planning and purchasing for this item. Those replaced items will not generate their own replenishment against that stock.
Example
You replace item A-100 with A-200. You still have 40 units of A-100 on the shelf at Dallas, and A-200 has 10 on hand.
Without inheritance: Recurrency plans A-200 as if only 10 units are available
With A-100 attached as an ancestor of A-200: effective net stock for A-200 at Dallas is 50 (10 + 40)
Planning recommendations and purchase needs for A-200 drop until that combined stock is consumed.
How to set it up
Open the replacement item (the one you want to replenish going forward).
Add the replaced item(s) as ancestors on that item.
Save. Recurrency applies the relationship to planning and purchasing.
💡 There is no separate on/off switch. Attaching ancestors turns inheritance on for that item.
Anyone who can edit items can manage stock inheritance relationships.
Tips for setup:
Attach ancestors on the current item — the one buyers order against
You can attach multiple replaced items to one replacement item
If an ancestor already has its own inheritance group, Recurrency merges and flattens the groups so stock still flows to one current item (no double counting)
You only need to attach the relevant top-level items; nested groups are flattened automatically
What changes in Recurrency
Planning
Recommendations use effective net stock instead of the item’s own stock alone
If leftover stock exists on replaced items, recommended buys and min/OP changes are reduced or removed until that stock is needed
Purchasing
Reorder logic also uses effective net stock
This helps prevent duplicate ordering across old and new item numbers during a transition
Hub and spoke
If you use hub-and-spoke, stock inheritance is applied first (per item and location). Hub/spoke aggregation then runs on that effective net stock — the same pattern you already use today.
Stock Inheritance vs Usage Inheritance
| Usage Inheritance | Stock Inheritance |
Purpose | Carry forward demand history from old items | Carry forward available inventory from old items |
Helps with | Forecasts, mins/OP, demand planning | Avoiding over-buys while old stock remains |
Required together? | No — configure each separately for the transition | No — configure each separately for the transition |
For a clean item supersedure, many teams set up both: usage so demand looks complete, and stock so supply is not ignored.
Important rules
Same location only — stock does not roll across branches
Same base UOM — items with mismatched units of measure cannot inherit (same rule as usage inheritance)
One destination — each replaced item can feed only one current item (stock cannot be split across two replacements)
Full inheritance — all of an ancestor’s net stock at that location is included (no partial / weighted share in v1)
Negative stock is included — if an ancestor is short, that shortfall is reflected in effective net stock
Deleted ancestors are ignored — items marked deleted (for example in P21) drop out of the set
Off by default — nothing changes until you attach ancestors
Frequently asked questions
Q: Does this change what I see on inventory screens?
A: Stock Inheritance is applied for planning and purchasing. Raw on-hand / inventory views may still show each item’s own stock. The inventory records themselves are not rewritten.
Q: Will Recurrency create a missing item-location so I can inherit stock?
A: No. If the replacement item does not exist at a location, stock stays with the ancestor at that location. Inheritance applies where both items have stock context at the same location.
Q: What if I already linked several old items in a chain?
A: You can attach items that themselves have ancestors. Recurrency flattens everything onto the current terminal item so planning stays simple and stock is counted once.
Q: Can two new items share stock from the same old item?
A: No. An ancestor can only belong to one descendant. That prevents the same units from being planned twice.
Q: Do I need Usage Inheritance turned on for Stock Inheritance to work?
A: No. They are independent relationships.
Q: Who can set this up?
A: Anyone with permission to edit items — the same permission used for other item-level changes.