You can define sourcing rules that specify how to replenish items in an organization, such as purchased items in plants. Sourcing rules can also specify how to replenish all organizations, as when the entire enterprise gets a subassembly from a particular organization.

If there is a conflict between a sourcing rule and a bill of distribution, the sourcing rule takes precedence.

1.1. Enter a unique sourcing rule name.

1.2. Indicate whether this sourcing rule is used for all organizations (global) or a single organization (local). If the sourcing rule is local, you must enter an organization name; otherwise, your current organization will be the receiving organization.
Here global means accross OUs. The same sourcing rule can be used in a differnt OU. If you make the sourcing rule as global then while selecting the supplier site we can choose a site from a differnt OU.

1.3. Choose Copy From to copy the effectivity dates and shipping organization from another sourcing rule into this one.

2.1. Enter effectivity dates. You must enter a start date, but entering an end date is optional.
For each range of effectivity dates, you can include multiple shipping organizations.
For each shipping organization you want to include, select a sourcing type to specify whether you make, buy, or internally transfer the item. You can also copy a list of shipping organizations from an existing sourcing rule. If you enter a customer organization as the receiving organization, then you cannot select a supplier organization as the shipping organization.

3.1. Enter an allocation percentage for each shipping organization. Allocation percentage includes the number of planned orders issued to the part for the entire the planning horizon. Your total allocation may not exceed 100. If the allocation percentage for all the shipping organizations included within a range of effectivity dates equals 100, Planning Active is checked. If the sourcing rule is not planning active, the planning process will not use the rule to assign planned orders.

3.2. Enter a numeric rank value to prioritize each sourcing type. If you have two sources with the same allocation percentage, planned orders are sourced from the highest rank first.

3.3. Select a shipping method, such as FEDEX, UPS, or rail