Assignment block filter field

Hi,

I searching already couple of weeks what I need to do to active the filter field on the assignment block level. In the customer system this field is not available right now alought the customer is on EHP3 SP 4. I assume that a business function is not active. But I'm not sure about.

Does anybody know how to activate the marked field?

cusersd056029desktopfilter-field.png

Thanks for you proomt answer

Br

Daniel