The Federal Trade Commission has just released some revisions of its decade-old online advertising guidelines, alliteratively titled “Dotcom Disclosures.” In it, the FTC lays out more specific rules for “space-constrained” ads, which you and me would probably just call Twitter ads.

The new regulations add bits and pieces about all types of online ads – especially ads viewed from mobile devices. But it’s the new guidelines on “space-constrained” ads (most applicable form being ads inside tweets) that are really interesting.

Of course, the FTC reminds us that all of the ad guidelines for all types of media apply to social media ads. Advertisers can’t hide the small print, and they can’t make it seem like the ad is not really an ad. But there are some specific guidelines for shorter ads, like the ones that appear on Twitter, that social media marketers need to know about.

First off, the FTC says that you can link to all the fine print instead of having to say it all inside the 140-character limit. But if you do, the click-through page must contain all applicable information and it must get to the point pretty quickly:

“When a space-constrained ad requires a disclosure, incorporate the disclosure into the ad whenever possible. However, when it is not possible to make a disclosure in a space-constrained ad, it may, under some circumstances, be acceptable to make the disclosure clearly and conspicuously on the page to which the ad links,” says the FTC.

But about that link: the FTC warns that shortened links like “bit.ly/f56” or even shortened links with the world “disclose” in them like “bit.ly/f56/disclose[6]” could confuse consumers. Simply put, the link may direct the consumer to the product’s website, but they wouldn’t know exactly why. Plus, it may be hard to find the disclosure.

Additionally, “space-constrained” advertisers run into another problem if their product is available to be purchased offline:

“If a product promoted in a space-constrained ad can be bought in a brick and mortar store, consumers who do not click through to a linked website would miss any disclosure that was not in the space-constrained ad itself. If the disclosure needs to be in the ad itself but it does not fit, the ad should be modified so it does not require such a disclosure or, if that is not possible, that space-constrained ad should not be used.”

Basically, the FTC is saying that if you can’t provide the fine print in your Twitter ad, and there’s a chance that a customer could buy your product offline without having seen the fine print, it’s best to simply forgo the Twitter ad altogether.

Even if the ad tweet is able to achieve this, the advertiser still has to adequately disclose that the viewer is in fact looking at an ad. The FTC suggests that adding “Ad:” to the beginning of the message or “Sponsored” somewhere inside would be sufficient. But one popular Twitter trick, adding “#spon” to ad tweets, could not be enough according to the FTC.

They say that it “might confuse consumers and make it less likely that they would understand that it is a disclosure.”

Of course, we’re not talking about Twitter’s official ad product here. Sponsored tweets are clearly marked as ads by Twitter themselves. What we’re talking about are unofficial “third-party” ads that users are paid to post. Twitter already requires that these third-party ads properly disclose that they are ads. But the FTC has clearly decided that there needs to be some hyper-specific rules for these new space-constrained ads, which we’ll only see more and more of in the coming years.