The article itself is old news, but it claims that Opera has spent zero on advertising:
Opera Software’s SVP Rod Hamlin: "Over our history, we've spent zero [on advertising], so it's a huge shift."
I'm not sure if he was misquoted (I guess so), but Opera Software has definitely spent money on advertising through the years. We may not have the advertising market locked down like Google does, or the financial power of other players in the market, but we have definitely been doing advertising.
And according to that article, we will spend even more on it in the future.