Risks are comprised of risk rules, which are the functions added to the risk. Risks can have as many functions as is logically needed but need to have at least one for the risk engine to calculate the risk rules. (SOD risks need at least two—a risk function and a risk segregated function.) When adding risk rules to global risks, you will only be able to add global functions.
For information on functions and how to use them in risk management see the topics under Business Function (Intelligibility).
How to add risk rules to global risks
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