Editor's note: This story was written several years ago and its information might be out of date. PrivacyDuck, a privacy service provider, maintains a free resource page with up-to-date opt-out instructions for dozens of data brokers.

Many women gamers and developers, as well as those who support them, have lately come under attack from online trolls. A common intimidation tactic that trolls use is "doxxing," or publicly exposing their targets' personal details, including home address, phone number and even financial records.

Doxxing is often accompanied by threats of violence, sexual assault or murder. The message is clear: We're out to get you, and we know where you live. Some women in tech have left their chosen profession rather than deal with continued threats.

But anyone is susceptible to doxxing, as game developer Phil Fish discovered this summer after speaking up in defense of a female developer. As the host of a feminist podcast, I decided to take the precaution of trying to remove public records of my whereabouts.

Unfortunately, doxxers don't have to work very hard to find a victim's personal info. A number of free and paid services known as data brokers create profiles of vast numbers of individuals based on aggregated data from business directories, social media and other public records. With a specific target in mind, all a doxxer has to do is search one or more of these services to find the details he or she wants.

More bad news: There are hundreds of data brokers, not all of which offer opt-out processes. (Exceptions are made for state-mandated protected groups, such as sexual assault survivors in California.) Removing yourself from all those that do can be a Sisyphean task, but managing your data with just the following 11 can be accomplished in an hour or two.

I selected these brokers based on the following factors:

What those who have been doxxed cited as services that were used against them

Search results for my own name

Consultation with Paul Stephens, director of policy and advocacy at the Privacy Rights Clearinghouse and author of Data Brokers and Your Privacy

Opt out of the following services, and you'll have "gotten all of the big ones," says Stephens—but pay attention to the caveat at the end of this story.

Note that some opt-out forms paradoxically require you to submit personal data in order to have it removed; be your own judge of whether this is wise. (I recommend creating a temporary email address specifically for these requests.)

Also note that with most of these services you'll receive a confirmation email shortly after you submit your removal request. If you don't see the email in your inbox, check your spam filter.

Here's what I found when I tried to opt out of each one.

Opt-out form: http://www.spokeo.com/opt_out/new

Verification needed: Email address

Promised turnaround time: 30 minutes

My opt-out result: Effective

Spokeo is used by many doxxers; fortunately, it has one of the easiest opt-out methods. Just search for yourself in the site's directory; when you find a record that matches your identity, copy the URL and submit it via the opt-out form. After you confirm your email address, your listing should be removed. Note that you may need to search by several criteria—name, email address, phone number(s), social media usernames—to find all your records.

Opt-out form: https://pipl.com/directory/remove/

Verification needed: Email address

Promised turnaround time: Immediate

My opt-out result: Effective

Pipl is both a search engine and a directory. While results cannot be blocked from the former, listings in the latter can be removed. First, manually craft a URL based on your name in the format of

https://pipl.com/n/firstname_lastname/

and paste it into the opt-out form. You'll see a list of people who share your name. You can then click "Remove" on any results that match your identity. You'll receive an email with a confirmation link.

Opt-out form: http://www.zoominfo.com/lookupEmail

Verification needed: Email address

Promised turnaround time: "Within a few days"

My opt-out result: Effective

ZoomInfo is a paid service that won't show you what it knows about you for free. It will acknowledge having your information on record, but only after you provide your email address. It will then send you an email message stating whether any matches were found—so if you no longer have access to the email address in ZoomInfo's database, you're out of luck.

If you do, and a record was found, opting out is as easy as clicking the confirmation link. But if ZoomInfo doesn't have a record of you, you'll still have given it your email address—and a temporary address created for this opt-out will naturally return no results.

ZoomInfo showed no records for me, so I opted out my father, who was listed. ZoomInfo now returns no search results for his email address.

Opt-out details: https://support.whitepages.com/hc/en-us/articles/203263794-How-do-I-remove-my-people-search-profile-

Verification needed: Email address and phone number

Promised turnaround time: Immediate

My opt-out result: Effective (but see note)

Up until recently, I had a listed landline. I now pay my phone company a monthly fee for an unlisted number, but it still showed up in places like Whitepages.

To find out if yours does, too, enter your name and address in the search box on the Whitepages home page. If you appear in the results, click the "Claim/Edit" button. Create an account and verify your email address. Whitepages will then ring the number listed in your profile. Just answer the phone and press "1." Once you hang up, you'll be able to use your online account's Privacy settings to unlist specific numbers or hide the entire profile.

Note: While Whitepages did honor my opt-out request, my record continued to show up in its search results via sponsored partners, such as BeenVerified.com, PeopleSmart.com and InstantCheckmate.com. Many of these sites have opt-out forms similar to the ones I've shared here; if you're truly committed to delisting yourself as completely as possible, you'll need to chase down these rabbit holes as you encounter them.

Opt-out form: https://www.peoplesmart.com/optout-go

Verification needed: Email address

Promised turnaround time: Up to 72 hours

My opt-out result: Effective

PeopleSmart is one of only two services on this list that requires you create an account in order to opt out. Once you find your record via the search box on the opt-out page, click "This is Me," create your account and confirm that you want to opt out; the service will send you a confirmation email.

If you do not have a record with PeopleSmart, you can request a manual opt-out by providing your contact information. Note that the company says, "It can take up to 7 days for us to process this type of request."

While PeopleSmart did remove its listing for Ken Gagne, it retained three additional listings for Kenneth Gagne. Once I'd created an account for Ken, I had to find and use a separate opt-out form for these variations on my name.

After you've done your opting out, be sure to adjust your account settings to not receive promotional emails.

Opt-out form: http://www.checkpeople.com/optout

Verification needed: None

Promised turnaround time: Up to 10 days

My opt-out result: Ineffective

CheckPeople.com is a paid service, but its search engine gives you a free glimpse of what it knows about you. In my case, it's an address I lived at 20 years ago and the names of everyone in my immediate family—including someone a relative was briefly married to more than a decade ago.

To opt out of CheckPeople.com, go to the opt-out form and submit your contact details. Despite the lengthy turnaround period, my first request was not effective. I've submitted a second one and have also taken advantage of the option of mailing a hard copy of my request, with which I included a printout of my result in the CheckPeople.com search engine.

Opt-out form: http://www.beenverified.com/optout

Verification needed: Email address

Promised turnaround time: 24 hours "in most cases"

My opt-out result: Effective

Opting out of BeenVerified is pretty painless. Submit your name and state to its opt-out form; if you find a matching profile, you can have it removed by verifying your email address.

Intelius and subsidiaries

Opt-out form: https://www.intelius.com/optout.php for Intelius; others below

Verification needed: Government-issued ID

Promised turnaround time: 7−14 days for Intelius; see others below

My opt-out result: Effective

Intelius is the parent company of many data brokers including PublicRecords360 and ZabaSearch, each of which must be opted out of individually. Fortunately, the process for each is similar. Unfortunately, it's the most onerous and aggressive process of any broker on this list, requiring a copy of your government-issued ID. You can block out your photo and driver's license number—only your name, address and birthdate are needed. But this means you can opt out using only the address on your current license; if your license is outdated, or if you want to remove an older address from the Intelius database, you're out of luck.

For Intelius itself, search for your public profile and, if you find it, go to the opt-out form and submit a scan of your ID.

PublicRecords360 also has an online opt-out form, but note that the form is powered by Google Docs. If you don't want corporate behemoths (including Google) to know your identity, then I recommend faxing your ID to 425-974-6194. (The opt-out form also says you can email your request to optout@publicrecords360.com—but the fine print states, "Requests for opt out will not be processed over the phone or via email.") PublicRecords360 says it will take 7 to 14 days to process the opt-out request.

While my opt-out requests with both Intelius and PublicRecords360 were effective, as with PeopleSmart, I needed to find and opt out of all variations on my name at each service.

Finally, ZabaSearch—a formerly independent service that has been acquired by Intelius—accepts requests only by fax, after which they take 4 to 6 weeks to process. There is no form or template to fill out for these requests, but again, a copy of your state ID is needed. I suggest finding your profile and including the URL with your request.

I didn't have a listing at ZabaSearch, nor did my father, so I can't report on the effectiveness of opt-out requests.

Intelius owns other data brokers, but these are the three that my sources referenced most often as likely to have my contact information.

Opt-out form: http://www.ussearch.com/privacylock

Verification needed: Government-issued ID

Promised turnaround time: Within 7−14 days of receipt of proof of identity

My opt-out result: N/A

US Search's database includes "addresses and phone numbers, social networking profiles, plus detailed background information available through public records." It used to charge for its opt-out service, which it calls PrivacyLock; now this service is free. But like ZabaSearch, it requires the offline submission of a copy of a government-issued ID.

After you enter your name, city, state and age in the initial PrivacyLock form and find your name in the results, click "This Is the Record I Would Like to Block." Then you must print a cover sheet with your record number on it, and fax or snail-mail it along with a copy of your ID.

Neither my father nor I had a listing at US Search, so I can't report on the effectiveness of opt-out requests.

Opt-out form: http://www.peoplefinders.com/manage/

Verification needed: None

Promised turnaround time: 1 hour

My opt-out result: Effective

To opt out of PeopleFinders, go to its opt-out page and search for your name, city and state. There may be multiple matches—for example, PeopleFinders found one record for me, but four for my father. Even though its privacy policy says the site "will only accept opt-out requests directly from the individual whose information is being opted-out," no verification is required, so for each match, I clicked "This is me" then "Opt out my info."

But that's not all: On the next screen you must enter a Recaptcha code, check a couple of disclaimer boxes and click Continue. And PeopleFinders.com isn't above upselling you during this free process. On the final opt-out screen, don't let the service gouge you $49.95 for a copy of your background report.

Opt-out form: http://www.peekyou.com/about/contact/optout/index.php

Verification needed: Email address

Promised turnaround time: Typically 48 hours; some take up to 10 business days

My opt-out result: Effective

PeekYou relies more on social media networks than on phone directories for its information, but it still helps tie together one's discrete identities into a single profile. You'll need to use the site's main search to find your profile's URL, such as http://www.peekyou.com/ken_gagne/352169778, and copy its numerical string (352169778) into the opt-out form, along with your name and email address. You'll have the choice to delist your age or your entire profile. A reason for removal is also required, though this can be as vague as "other."

Final words

Unfortunately, opting out is not a one-time process. "Even though you've opted out, these sites may refresh their data from new information that comes in," says Stephens of the Privacy Rights Clearinghouse. Anytime your phone number or address changes or your information becomes available from a new broker, your details may propagate to services you've previously opted out of. One need look no further than the fine print at Whitepages.com for an example, as the site warns: "Whitepages continuously discovers new information, so please check back regularly to make sure your information is shown correctly."

But such vigilance can help avoid even worse outcomes. Few people are more familiar with the consequences of being doxxed than independent game developer Zoe Quinn, who was doxxed in August and has since tolerated months of threats and harassment. Her recent Tumblr post "What To Expect When You're Expecting (the internet to ruin your life)" offers additional advice for obscuring private data, including removing your WHOIS info, checking your Facebook privacy settings, changing your security questions and enabling two-factor authentication.

See our three-part series, "The paranoid's survival guide," for more steps you can take to protect your personal information:

It's almost impossible to remove all traces of your existence from the Internet—but with these steps, you can at least feel safer in your own home.