Stock posting (BSX) - This transaction is used for all postings to stock accounts. Such postings are effected, for example: 
In inventory management in the case of goods receipts to own stock and goods issues from own stock.
In invoice verification, if price differences occur in connection with incoming invoices for materials valuated at moving average price and there is adequate stock coverage.
In order settlement, if the order is assigned to a material with moving average price and the actual costs at the time of settlement vary from the actual costs at the time of goods receiptBecause this transaction is dependent on the valuation class, it is possible to manage materials with different valuation classes in separate stock accounts. 

Caution:
Take care to ensure that:
A stock account is not used for any transaction other than BSX.
Postings are not made to the account manually.
The account is not changed in the productive system before all stock has been booked out of it.

Otherwise differences would arise between the total stock value of the material master records and the balance on the stock account.

Offsetting entry for stock posting (GBB) - Offsetting entries for stock postings are used in Inventory Management. They are dependent on the account grouping to which each movement type is assigned. The following account groupings are defined in the standard system: 

• AUA: for order settlement
• AUF: for goods receipts for orders (without account assignment) and for order settlement if AUA is not maintained
• AUI: Subsequent adjustment of actual price from cost center directly to material (with account assignment)
• BSA: for initial entry of stock balances
• INV: for expenditure/income from inventory differences
• VAX: for goods issues for sales orders without account assignment object (the account is not a cost element) 
• VAY: for goods issues for sales orders with account assignment object (account is a cost element)
• VBO: for consumption from stock of material provided to vendor
• VBR: for internal goods issues (for example, for cost center) 
• VKA: for sales order account assignment (for example, for individual purchase order)
• VKP: for project account assignment (for example, for individual PO)
• VNG: for scrapping/destruction
• VQP: for sample withdrawals without account assignment 
• VQY: for sample withdrawals with account assignment
• ZOB: for goods receipts without purchase orders (mvt type 501)
• ZOF: for goods receipts without production orders (mvt types 521 and 531)

Caution:
If you use goods receipts without a purchase order in your system (movement type 501), you have to check to which accounts the account groupings are assigned ZOB.
If you expect invoices for the goods receipts, and these invoices can only be posted in Accounting, you can enter a clearing account (similar to a GR/IR clearing account though without open item management), which is cleared in Accounting when you post the vendor invoice. 
Note that the goods movement is valuated with the valuation price of the material if no external amount has been entered.
As no account assignment has been entered in the standard system, the assigned account is not defined as a cost element. If you assign a cost element, you have to enter an account assignment via the field selection or maintain an automatic account assignment for the cost element. 

GR/IR clearing (WRX) - Postings to the GR/IR clearing account occur in the case of goods and invoice receipts against purchase orders. 
Caution:
You must set the Balances in local currency only indicator for the GR/IR clearing account to enable the open items to be cleared. 

Price differences (PRD) - Price differences arise for materials valuated at standard price in the case of all movements and invoices with a value that differs from the standard price. Examples: goods receipts against purchase orders (if the PO price differs from the standard pricedardpreis), goods issues in respect of which an external amount is entered, invoices (if the invoice price differs from the PO price and the standard price).

Price differences can also arise in the case of materials with moving average price if there is not enough stock to cover the invoiced quantity. In the case of goods movements in the negative range, the moving average price is not changed. Instead, any price differences arising are posted to a price difference account. 
Depending on the settings for the posting rules for transaction/event key PRD, it is possible to work with or without account modification. If you use account modification, the following modifications are available in the standard system: 
None for goods and invoice receipts against purchase orders.

Purchase account(EIN), purchase offsetting account (EKG), freight purchase account (FRE) 
These transactions are used only if Purchase Account Management is active in the company code.

Note
Due to special legal requirements, this function was developed specially for certain countries (Belgium, Spain , Portugal, France, Italy, and Finland).
Before you use this function, check whether you need to use it in your country.

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