[GNC] Transaction regex help

[Michelle]

I've been bashing my head against this for a while.

I'm after a grocery report, so I want everything that I buy from
Sainsburys, M&S, Iceland... but not if it is clothes.

I've got as far as picking out all the stores using Regex in the
transaction filter...

Sainsburys|Iceland|Marks & Spencer

...but I can't figure out how to include, Not Clothing.

I have tried various variants including negative lookahead, but I'm
obviously doing something wrong...
(Sainsburys|Iceland|Marks & Spencer)(?!Clothing)

Grateful for any advice please.

Michelle.