This example uses the UNIQUE function together with the FILTER function. The FILTER function removes data that does not meet required criteria, and the UNIQUE function further limits results to unique values only.

Working from the inside out, the FILTER function is used to collect source data in group B with a quantity greater than 5:

FILTER(B5:B16,(C5:C16="b")*(D5:D16>5)) // group is b, qty over 5

Insider filter, the expression used for the include argument:

 (C5:C16="b")*(D5:D16>5)

This is an example of using boolean logic to construct required logical criteria. The result is a boolean array like this:

{0;1;0;0;0;1;0;1;0;0;1;1}

This array is used to filter data, and the FILTER function returns another array as a result:

{"amber";"purple";"purple";"pink";"pink"}

This array is returned to the UNIQUE function as the array argument. UNIQUE then removes duplicates, and returns the final array:

{"amber";"purple";"pink"}

UNIQUE and FILTER are dynamic functions. If source data changes, output will update immediately.