Add a filter in the Program/Campaign Smart List to include the static list.
The trick will be to make sure the filter logic is correct. Advanced Logic may need to be used in the Smart List of the Program/Campaign.
For example, if there's a sending campaign with 5 filters to send to an audience
1 AND 2 AND 3 AND (4 OR 5)
then you will want to use Advanced Logic and put parentheses around the original filter set
(1 AND 2 AND 3 AND (4 OR 5))
and add the seed list outside the parentheses with OR logic
(1 AND 2 AND 3 AND (4 OR 5)) OR 6
In that advanced logic, the original intended membership (1 through 5) exist within its own set of parentheses and the Seed List is included in addition (OR 6).