Weighted average Cost and ST/OT

We have the following scenario: Several Branch/plants, the plants buy the raw materials from suppliers. The raw materials are valued at standard costs (07) in all plants. All plants have the same standard costs for the same raw material. However, it also happens that raw materials are transferred between the plants via ST/OT. The transfer is made at standard cost 07 (Price ST = Cost in OT). The problem: The goods receipt of the OT changes the 02 costs in the receiving plant. This distorts them! Question: Is there a way to prevent the update of the 02 cost when