As a way of tracking possible spam and simply keeping one’s inbox organized, a small but growing number of people are adding “+” terms onto their e-mail addresses when they register with websites. But one Consumerist reader says that when he tried to use this technique to keep track of e-mails related to his Zillow.com account, that account was suspended for violating the company’s trademark.

Miles tells Consumerist that when he signed up with the real estate listings site, he added the term “+zillow” between his e-mail user ID and the “@” sign. Doing so would allow him to set up a rule that would tag or filter all e-mails coming to that address.

It’s becoming a more common practice as consumers use it, especially with e-commerce sites, to prioritize and sort their incoming messages.

But to Zillow, it’s a trademark violation, one that resulted in Miles’ account being suspended.

A rep for the site confirmed to Consumerist that this is indeed company policy:

Trademarks are used to designate the origin of products and/or services. Using a Zillow trademark as part of a Zillow user’s account name has the potential to mislead or confuse other users into thinking that the user is affiliated with or endorsed by Zillow. In order to maintain one’s trademark rights, a trademark registrant must exercise control to ensure that its mark is used only to designate the origin of the products and/or services that it was registered to identify.

When we pointed out that the “+zillow” would not appear in the user name on the site, the rep replied:

We have no way of knowing how someone will use the email address that they use to sign up for a Zillow account. A real estate agent could distribute it widely as their professional email (which has happened) or a non-agent user could use it solely for receiving emails from Zillow. This is not within our control. What is within our control is whether we allow someone to use the Zillow trademark on the Zillow website in a way that is not specifically designating Zillow products and/or services. Not permitting such use is Zillow’s right and responsibility as a trademark registrant.

As for Miles, he tells Consumerist he’s not terribly worked up about it because he can easily just sign up again with a different e-mail, “but it’s a dumb corporate policy to treat people like this.”

To avoid falling into the same trap, we suggest people use something other than the site’s name when adding the “+” term. So instead of using “+zillow,” use “+realty” or some other indicator that will make it easy for you to figure out which site that e-mail is related to.

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