What you need is a table calculation which looks at each manufacturer and decides which is highest per hospital.
Create a calculated field on Sales (or whatever your measure is called) as follows:
This gives a true/false measure which you can use as a filter. You must set the compute method for the table calc to use Manufacturer. See the attached workbook for an example using the superstore sales data set.
Max sales.twbx.zip 1.2 MB
Perfect, thanks Robin!