How to negate filter condition?

Is it possible to negate the condition of a filter?

Lets say I want to get all companies except those with the ids 1 and 2. Could I do something similar to this?

http://www.giantbomb.com/api/companies/?api_key=YOUR_KEY&format=json&field_list=id,name&filter=id:!1|!2

is there any way to accomplish this?

I have not seen a feature like this. But its of course possible if you cache the companies on your site first.