No, a guild may not have a contest, the rules are the same for the entire site. It's in the T&C and there was an entire article on Guilds in the Neopets Magazine, Issue 6 (pirate lupe on the cover). This is from the article (I'm not going to try to type the whole thing)
Quote:
So, just to recap:
A contest is an activity where the participants are offered (or promised) the possibility of receiving a prize in exchange for participating in (or "winning") that activity. This is NOT allowed on the Neopets site.
A competition is an activity in which participants are never offered (or promised) the possibility of receiving a prize in exchange for their involvement. They participate solely because they want to. This IS allowed by the Neopets site. Keeping this in mind, should the proprietor of a guild decide to give an item(s) to someone who happened to be a participant in one of their competitions, then this is okay, as there are no rules against this on the Neopets site.
Also, new member packs, birthday packs, motw, motm, things like that are not allowed, they are considered giveaways.
Our guild leader and co-leader had many email correspondence with different Staff asking them about donations, raffles, contests, giveaways, the packs, etc. and both were told by various Staff that those things are not allowed.
I would not want to see anything happen to anyone who is owner, on council or just a member of any guild. That's the reason I brought this up in the first place. I've seen the boards of guild members saying their leader and council were all frozen, the guild deleted because of contests, etc. And I've seen people get warnings for saying their guild has contests, parties, etc. It's just not worth it.