What to Know About Cellphone Radiation

ProPublica recently examined how the federal government, based on quarter-century-old standards, denies that cellphones pose any risks. This guide answers some of the most common questions people ask about cellphone radiation.

Inside Google’s Quest to Digitize Troops’ Tissue Samples

The tech giant has long sought access to a priceless trove of veterans’ skin samples, tumor biopsies and slices of organs. DOD staffers have pushed back, raising ethical and legal concerns, but Google might win anyway.

Fintechs Made “Massive Profits” on PPP Loans and Sometimes Engaged in Fraud, House Committee Report Finds

An investigation that began after reporting by ProPublica finds lax anti-fraud standards, executives who cashed in for themselves and contempt for small loan applications that would generate minimal fees. “Delete them,” one executive wrote.

Department of Justice Opens Investigation Into Real Estate Tech Company Accused of Collusion with Landlords

The DOJ will examine whether RealPage helped landlords coordinate rent increases. Questions also swirl around a 2017 merger deal with its largest competitor.

More Senate Democrats Seek Investigation of Tech Firm Accused of Colluding With Landlords to Hike Apartment Rents

Sen. Amy Klobuchar and other leading Democrats have asked the Department of Justice to examine Texas-based RealPage, which sells software to help landlords set apartment rental prices across the country.

Pressure Grows on Real Estate Tech Company Accused of Colluding With Landlords to Jack Up Apartment Rents

RealPage has come under increasing fire from lawmakers and lawyers after ProPublica reported on its software’s potentially anti-competitive effects. Student housing is implicated.

How the FCC Shields Cellphone Companies From Safety Concerns

The wireless industry is rolling out thousands of new transmitters amid a growing body of research that calls cellphone safety into question. Federal regulators say there’s nothing to worry about — even as they rely on standards established in 1996.

How Google’s Ad Business Funds Disinformation Around the World

The largest-ever analysis of Google’s ad practices on non-English-language websites reveals how the tech giant makes disinformation profitable.

Company That Makes Rent-Setting Software for Apartments Accused of Collusion, Lawsuit Says

Texas-based RealPage worked with some of the nation’s largest landlords to create a cartel to raise rents, says a lawsuit filed just days after ProPublica published its investigation into the company.

How the FBI Stumbled in the War on Cybercrime

In this excerpt from “The Ransomware Hunting Team: A Band of Misfits’ Improbable Crusade to Save the World From Cybercrime,” the authors reveal how unprepared the nation’s top federal law enforcement agency was to combat online crime.

Rent Going Up? One Company’s Algorithm Could Be Why.

Texas-based RealPage’s YieldStar software helps landlords set prices for apartments across the U.S. With rents soaring, critics are concerned that the company’s proprietary algorithm is hurting competition.

Human Trafficking’s Newest Abuse: Forcing Victims Into Cyberscamming

Tens of thousands of people from across Asia have been coerced into defrauding people in America and around the world out of millions of dollars. Those who resist face beatings, food deprivation or worse.

He Felt Isolated and Adrift After an Autism Diagnosis. Can He Make It as a Cybersleuth?

Highly educated autistic people have long found work in tech — but now two Dutch entrepreneurs are training socially isolated autistic dropouts and finding productive jobs for them. The approach could be a model for America.

Real Money, Fake Musicians: Inside a Million-Dollar Instagram Verification Scheme

A jeweler. A plastic surgeon. An OnlyFans Model. They and others received a blue check in likely the biggest Instagram verification scheme revealed to date. After ProPublica started asking questions, Meta removed badges from over 300 accounts.

Federal Patient Privacy Law Does Not Cover Most Period-Tracking Apps

A patient privacy law known as HIPAA, passed in 1996, hasn’t kept pace with new technologies and at-home tests.

Google Allowed a Sanctioned Russian Ad Company to Harvest User Data for Months

The internet giant may have provided Sberbank-owned RuTarget with unique mobile phone IDs, IP addresses, location information and details about users’ interests and online activity.

Facebook Finally Agrees to Eliminate Tool That Enabled Discriminatory Advertising

Six years after ProPublica revealed that Facebook allowed advertisers to exclude Black users and others, the company agreed to a settlement with the Justice Department to overhaul its ad algorithm system.

“Big Lie” Vigilantism Is on the Rise. Big Tech Is Failing to Respond.

Stolen-election activists and Trump supporters have embraced a new tactic in their campaign to unearth supposed proof of fraud in the 2020 presidential race: using social media to chase down a fictional breed of fraudster known as a “ballot mule.”

Inside the Government Fiasco That Nearly Closed the U.S. Air System

The upgrade to 5G was supposed to bring a paradise of speedy wireless. But a chaotic process under the Trump administration, allowed to fester by the Biden administration, turned it into an epic disaster. The problems haven’t been solved.

How Your Shadow Credit Score Could Decide Whether You Get an Apartment

The vast tenant screening industry is subject to less regulation than credit scoring agencies, even though experts warn that algorithms could introduce racial or other illegal biases that can prevent people from getting housing.

Congressional Chair Asks Google and Apple to Help Stop Fraud Against U.S. Taxpayers on Telegram

After ProPublica investigations revealed thriving cybermarkets on Telegram where fraudsters buy and sell stolen personal information for unemployment insurance fraud, Rep. James Clyburn is hoping to enlist Apple and Google in the fight.

In the Ukraine Conflict, Fake Fact-Checks Are Being Used to Spread Disinformation

Social media posts debunking purported Ukrainian disinformation are themselves fake. That doesn’t stop them from being featured on Russian state TV.

How Bots and Fake Accounts Push China’s Vision of Winter Olympic Wonderland

Online, the country’s propagandists have promoted a vision of the Games free of hostility or controversy. For example: The New York Times and ProPublica have identified over 3,000 inauthentic-looking Twitter accounts that appear in on the effort.

A Former Hacker’s Guide to Boosting Your Online Security

More stolen personal data is available online than ever before. A man who once ran a website that prosecutors called the Amazon of stolen identity information offers his tips on the best ways to protect your data.

Despite Decades of Hacking Attacks, Companies Leave Vast Amounts of Sensitive Data Unprotected

A surge in identity theft during the pandemic underscores how easy it has become to obtain people’s private data. As hackers are all too happy to explain, many of them are cashing in on it.

Boston City Councilors Seek Review of Surveillance Tech Purchase by Police

After a WBUR/ProPublica investigation revealed Boston Police bought spy tech using funds hidden from the public, city legislators called for a review of the transaction.

The Extortion Economy Podcast: Exploring the Secret World of Ransomware

The technology that enables ransomware may be new, but extortion and ransom are not. So why is this happening now? And can it be stopped? A new podcast from ProPublica and MIT Tech Review aims to find out.

Boston Police Bought Spy Tech With a Pot of Money Hidden From the Public

Massachusetts police can seize and keep money from drug-related arrests. No one has publicly reported how that money gets spent. A WBUR/ProPublica investigation found that Boston police used over $600,000 of it on a controversial surveillance device.

China Unleashed Its Propaganda Machine on Peng Shuai’s #MeToo Accusation. Her Story Still Got Out.

Chinese propaganda officials have tried to shape the global discussion of the tennis player Peng Shuai’s accusations and disappearance, but their top-down strategy has largely stumbled.

How Steve Bannon Has Exploited Google Ads to Monetize Extremism

Google kicked Bannon off YouTube because of his violent rhetoric but still sent ad dollars to his website that promotes misinformation about the election and the pandemic.

How to Avoid Being Scammed by Fake Job Ads

Phony job advertisements are proliferating on the internet, often as part of identity-theft schemes. Here’s how to avoid falling victim to them.

Scammers Are Using Fake Job Ads to Steal People’s Identities

From Facebook to LinkedIn to Indeed, ads are popping up that promise well-paying jobs — if applicants provide their Social Security numbers and other details up front. Scammers then use the information to apply for unemployment benefits.

How to Avoid Being Scammed on Facebook Marketplace

From suspiciously low prices to sellers who demand payment in gift cards, there are multiple warning signs a Marketplace listing might be fraudulent.

Facebook Grew Marketplace to 1 Billion Users. Now Scammers Are Using It to Target People Around the World.

ProPublica identified thousands of Marketplace listings and profiles that broke the company’s rules, revealing how Facebook failed to safeguard users.

How Facebook Undermines Privacy Protections for Its 2 Billion WhatsApp Users

WhatsApp assures users that no one can see their messages — but the company has an extensive monitoring operation and regularly shares personal information with prosecutors.

Senate Banking Chair Asks CFPB How It Plans to Address Risks of Chime and Other Banking Apps

Citing a ProPublica report on the high numbers of complaints about involuntary Chime account closures and other problems, Sherrod Brown asked the Consumer Financial Protection Bureau to lay out a plan for overseeing neobanks.

A Banking App Has Been Suddenly Closing Accounts, Sometimes Not Returning Customers’ Money

Chime, a “neobank” serving millions, is racking up complaints from users who can’t access their cash. The company says it’s cracking down on an “extraordinary surge” in fraudulent deposits. That’s little consolation to customers caught in the fray.

How China Spreads Its Propaganda Version of Life for Uyghurs

Thousands of videos of Uyghurs denying abuses against their community are showing up on Twitter and YouTube. They’re part of an elaborate influence campaign by Chinese officials to counter reports of human rights violations in Xinjiang.

The Colonial Pipeline Ransomware Hackers Had a Secret Weapon: Self-Promoting Cybersecurity Firms

Five months before DarkSide attacked the Colonial pipeline, two researchers discovered a way to rescue its ransomware victims. Then an antivirus company’s announcement alerted the hackers.

Addressing Rape in Four Minutes or Less: Dating App Reps Left Unprepared to Respond to Assault Victims

At OkCupid and other dating apps, moderators are expected to resolve customer claims of sexual assault in minutes — and with no special training.

Senator Says Censorship in Turkey Raises “Serious Questions” About Facebook's Commitment to Free Expression

After ProPublica reported that Facebook blocked a militia group targeted by Turkish forces, the chair of the Senate Finance Committee demanded that Mark Zuckerberg provide answers to more than a dozen questions.

Tinder and OkCupid Could Soon Let You Background Check Your Date — for a Price

Dogged by questions about sexual violence, Match Group — which owns Tinder, Hinge, Match.com, OkCupid, PlentyofFish and others — is investing in a company that aims to enable background checks on apps. Some legislators say it’s not enough.

America’s Drinking Water Is Surprisingly Easy to Poison

The cyberbreach at a plant in Oldsmar, Florida, which could have resulted in a mass poisoning, was a reminder of a disturbing reality: Despite a decade of warnings, thousands of water systems around the country are still at risk.

Sheryl Sandberg and Top Facebook Execs Silenced an Enemy of Turkey to Prevent a Hit to the Company’s Business

Amid a 2018 Turkish military campaign, Facebook ultimately sided with Turkey’s demand to block the page of a mostly Kurdish militia. “I am fine with this,” Sandberg wrote.

Twenty-Six Words Created the Internet. What Will It Take to Save It?

Jeff Kosseff wrote the book on Section 230, the law that gave us the internet we have today. He talks with ProPublica Editor-in-Chief Stephen Engelberg about how we got here and how we should regulate our way out.

The U.S. Spent $2.2 Million on a Cybersecurity System That Wasn’t Implemented — and Might Have Stopped a Major Hack

The software company SolarWinds unwittingly allowed hackers’ code into thousands of federal computers. A cybersecurity system called in-toto, which the government paid to develop but never required, might have protected against this.

Leaked Documents Show How China’s Army of Paid Internet Trolls Helped Censor the Coronavirus

As the coronavirus spread in China, the government stage-managed what appeared on the domestic internet to make the virus look less severe and the authorities more capable, according to thousands of leaked directives and other files.

Trump Won Florida After Running a False Ad Tying Biden to Venezuelan Socialists

A Trump video targeting Florida’s growing Venezuelan American population falsely claimed that Venezuela’s socialist regime wanted Biden to win. But President Nicolás Maduro has said that he opposed both candidates.

Trump ganó Florida tras publicar un anuncio falso que vinculaba a Biden con los socialistas venezolanos

Un anuncio de Trump dirigido a la creciente población venezolano-estadounidense de Florida declaró falsamente que el régimen socialista de Venezuela quería que Biden ganara. Pero el presidente Nicolás Maduro ha dicho que se opone a ambos candidatos.

Al menos 800,000 residentes de estados clave recibieron robocalls pidiéndoles que se “quedaran en casa” el día de las elecciones. El FBI está investigando.

Una empresa que rastrea las llamadas automatizadas, conocidas en inglés como *robocalls*, dijo que se hicieron más de tres millones de llamadas el 3 de noviembre que contenían un mensaje críptico, instando a la gente a “permanecer seguros y quedarse en casa". Las tácticas se suman a otras que buscan confundir a los votantes en este ciclo electoral.

Robocalls Told at Least 800,000 Swing State Residents to “Stay Home” on Election Day. The FBI Is Investigating.

A firm that tracks robocalls said more than 3 million calls were made on Nov. 3, which contained a cryptic message instructing people to “stay safe and stay home.” The tactics join other efforts to confuse voters this election cycle.

Foreign Hackers Cripple Texas County’s Email System, Raising Election Security Concerns

The malware attack, which sent fake email replies to voters and businesses, spotlights an overlooked vulnerability in counties that don’t follow best practices for computer security.

Facebook’s Political Ad Ban Also Threatens Ability to Spread Accurate Information on How to Vote

Two months out from Election Day, Facebook’s changes to its political ad rules cause additional problems for the government officials running the vote.

Amazon’s New Competitive Advantage: Putting Its Own Products First

Brands have long been able to bid for the premier slot at the top left of Amazon’s listings, but during the pandemic the online retailer has begun using this position for its private-label items, raising antitrust concerns.

Millions of Americans Might Not Get Stimulus Checks. Some Might Be Tricked Into Paying TurboTax to Get Theirs.

Congress gave the IRS the job of sending out coronavirus rescue checks. But the underfunded agency is struggling, while for-profit companies like Intuit have started circling, hoping to convert Americans in need into paying customers.

The Hate Store: Amazon’s Self-Publishing Arm Is a Haven for White Supremacists

The company gives extremists and neo-Nazis banned from other platforms unprecedented access to a mainstream audience — and even promotes their books.

When the State Shifted to E-learning, This Rural School Superintendent Shifted to the Copy Machine

With schools closed because of coronavirus, students are expected to learn remotely. But what happens when your school district doesn’t have the internet access to keep you in school? Here’s one district’s paper trail.

Some Election-Related Websites Still Run on Vulnerable Software Older Than Many High Schoolers

Our analysis found that websites in dozens of towns and counties voting on Super Tuesday have security weaknesses. Richmond, Va., still uses software from 2003.

TurboTax Is Still Tricking Customers With Tax Prep Ads That Misuse the Word “Free”

Intuit has amped up its misleading digital advertising in the wake of a new IRS agreement that bars tax prep companies from burying the agency’s Free File program.

Dating Apps Can Be Dangerous. Congress Is Investigating.

Prompted by press reports, including a recent article by Columbia Journalism Investigations and ProPublica, a House subcommittee announced that it would examine the use of dating apps by minors and the prevalence of sex offenders on such sites.

The IRS Decided to Get Tough Against Microsoft. Microsoft Got Tougher.

For years, the company has moved billions in profits to Puerto Rico to avoid taxes. When the IRS pushed it to pay, Microsoft protested that the agency wasn’t being nice. Then it aggressively fought back in court, lobbied Congress and changed the law.

Like Voldemort, Ransomware Is Too Scary to Be Named

Wary of alarming investors, companies victimized by ransomware attacks often tell the SEC that “malware” or a “security incident” disrupted their operations.

Kansas Abandons Technology Trumpeted by Kris Kobach, Trump’s Onetime Voter Fraud Czar

A system supposedly meant to root out voter fraud was beset by security and accuracy issues.

YouTube Promised to Label State-Sponsored Videos But Doesn’t Always Do So

We found more than 50 government-funded channels from countries including Russia, Iran and the United States that the Google subsidiary failed to flag.

The Ransomware Superhero of Normal, Illinois

Thanks to Michael Gillespie, an obscure programmer at a Nerds on Call repair store, hundreds of thousands of ransomware victims have recovered their files for free.

Millions of Americans’ Medical Images and Data Are Available on the Internet. Anyone Can Take a Peek.

Hundreds of computer servers worldwide that store patient X-rays and MRIs are so insecure that anyone with a web browser or a few lines of computer code can view patient records. One expert warned about it for years.

Report on Election Security Gains Attention, and a Sharp Rebuke

A Virginia cybersecurity company asserted many states were vulnerable to election system intrusions. Critics called the report flawed and questioned whether the company was looking to exploit legitimate anxiety about election security.

How Kentucky Gambled for Hundreds of Millions of Dollars From a Broadband Program It Didn’t Qualify for

Former Gov. Steve Beshear’s administration was warned multiple times that its rural broadband bet wouldn’t get certain federal funds. Meet the officials and conflicted consultants who didn’t listen and doomed the plan.

How Amazon and Silicon Valley Seduced the Pentagon

Tech moguls like Jeff Bezos and Eric Schmidt have gotten unprecedented access to the Pentagon. And one whistleblower who raised flags has paid the price.

New York Is Investigating Whether Facebook Lets Advertisers Discriminate

The state’s Department of Financial Services will look into allegations, first exposed by ProPublica, that advertisers can exclude users by race, gender, age and other characteristics that are protected under federal law.

Civil Rights Groups Have Been Warning Facebook About Hate Speech In Secret Groups For Years

Facebook says its rules prohibit hate in secret groups, but it won’t discuss how it moderated the offensive Border Patrol posts — if it did anything at all.

Sting Catches Another Ransomware Firm — Red Mosquito — Negotiating With “Hackers”

We recently wrote about two U.S. firms that promised high-tech ransomware solutions but instead paid the cyber-attacker. A U.K. company appears to do the same.

We’re Reporting on Ransomware. Do You Know Something About an Attack?

Has your organization been hit by ransomware? Did you hire a data recovery firm? Do you know how an attack works from the inside? We’d like to hear from you.

A High-Speed Internet Boondoggle Is Now a Campaign Issue in Kentucky

Governor Matt Bevin's opponents on both sides of the aisle are coming after him for failing to address KentuckyWired delays.

Kentucky’s $1.5 Billion Information Highway to Nowhere

Gov. Matt Bevin has offered no solution to the boondoggle he inherited, a plan to bring high-speed internet to Kentucky’s remote corners.

The Missing Millions: Some States Are Still Waiting for the Gambling Windfall

Prosecutors Dropping Child Porn Charges After Software Tools Are Questioned

More than a dozen cases were dismissed after defense attorneys asked to examine, or raised doubts about, computer programs that track illegal images to internet addresses.

HUD Sues Facebook Over Housing Discrimination and Says the Company’s Algorithms Have Made the Problem Worse

The charge comes a week after Facebook made major changes to its advertising platform, and two years after our reporting raised the issue.

Legalized Betting Could Change How We Watch Sports

Facebook Won’t Let Employers, Landlords or Lenders Discriminate in Ads Anymore

The sweeping changes come two years after ProPublica’s reporting, which sparked lawsuits and widespread outrage.

Facebook and Twitter Turned to TurboVote to Drive Registrations. Officials Want Them to Turn Away.

The National Association of Secretaries of State is asking the social media companies to direct prospective voters to government sites after claims TurboVote occasionally failed to properly process registrations, among other missteps.

Facebook Moves to Block Ad Transparency Tools — Including Ours

Our tool had let the public see exactly how users were being targeted by advertisers. The social media giant urged us to shut it down last year.

Georgia Officials Quietly Patched Security Holes They Said Didn’t Exist

A ProPublica analysis found that the state was busily fixing problems in its voter registration hours after the office of Secretary of State Brian Kemp, the Republican candidate for governor, had insisted the system was secure.

How Big Oil Dodges Facebook’s New Ad Transparency Rules

We’ve identified 12 ad campaigns in which energy, insurance and other industries masked their sponsorship of political messages on Facebook.

Why Am I Seeing This? Interesting Facebook Ads From Our Political Ad Collector

We’re highlighting examples from our Facebook political ad collection that are interesting because of how they’re targeted, what they say or how they can help explain how Facebook’s advertising system works — and how it can be gamed.

Facebook Is Letting Job Advertisers Target Only Men

A review by ProPublica found that 15 employers in the past year, including Uber, have advertised jobs on Facebook exclusively to one sex, with many of the ads playing to stereotypes.

The Overlooked Weak Link in Election Security

While attention has focused on the potential to penetrate voting machines, a ProPublica survey found that more than one-third of counties overseeing toss-up congressional elections have email systems that could be vulnerable to hacking.

D.C.-Based Pro-Israel Group Secretly Ran Misleading Facebook Ads to Target Pro-Palestinian Activist

The well-funded group behind the campaign, the Israel On Campus Coalition, has links to the Israeli government.

No, a Teen Did Not Hack a State Election

Hacking conference organizers said kids had hacked “exact clones” of state election reporting websites, but that didn’t happen.

Besieged Facebook Says New Ad Limits Aren’t Response to Lawsuits

The social network is removing 5,000 options that regulators say enable advertisers to discriminate.

Facebook Promises to Bar Advertisers From Targeting Ads by Race or Ethnicity. Again.

Settling an investigation by the state of Washington prompted by a ProPublica story, the social networking company said it would no longer allow advertisers to exclude users by any federally protected categories.

Facebook’s Screening for Political Ads Nabs News Sites Instead of Politicians

The social network is letting some political ads slip through without the required verification, while blocking promotional posts by news organizations, which are pushing back.

What Facebook’s New Political Ad System Misses

Facebook announced a new system to make political ads more transparent. It’s got holes.

How to Wrestle Your Data From Data Brokers, Silicon Valley — and Cambridge Analytica

It can be done but it’s not easy.

For Some Democrats, Facebook Likes Are a Path to Hard-to-Find Supporters

The Arizona special election campaign of Hiral Tipirneni targeted ads at people across the country who “liked” the pages of liberal icons.

We Have Some Follow-Ups for Facebook — And We Want Your Help

Senators held Facebook’s Mark Zuckerberg to account today, grilling him while often citing our investigations. You can help keep Facebook accountable, too.

Four Ways to Fix Facebook

For years, Congress and federal regulators have allowed the world’s largest social network to police itself — with disastrous results. Here are four promising reforms under discussion in Washington.

Outlets in Eight Countries Are Using Our Tool to Monitor Political Ads on Facebook

From Australia to Scandinavia, our Political Ad Collector is holding advertisers accountable by revealing pitches that only a targeted slice of Facebook users would otherwise see.

Facebook’s Experiment in Ad Transparency Is Like Playing Hide And Seek

Starting in Canada, Facebook is rolling out a global program to prevent foreign meddling in elections. Ads targeted to a narrow audience may be seen by other Facebook users — if they look hard enough.

ProPublica Seeks Source Code for New York City’s Disputed DNA Software

We’re asking a federal court for the code behind a technique that critics say may have put innocent people in prison.

Despite Disavowals, Leading Tech Companies Help Extremist Sites Monetize Hate

Most tech companies have policies against working with hate websites. Yet a ProPublica survey found that PayPal, Stripe, Newsmax and others help keep more than half of the most-visited extremist sites in business.

How We Investigated Technology Companies Supporting Hate Sites

We wrote software to find the external domains contacted by popular websites that have been identified as extremist by either the Southern Poverty Law Center or the Anti-Defamation League.

Service Provider Boots Hate Site Off the Internet

The web services company Cloudflare appears to have ended its relationship with the neo-Nazi website The Daily Stormer.

Facebook’s Secret Censorship Rules Protect White Men From Hate Speech But Not Black Children

A trove of internal documents sheds light on the algorithms that Facebook’s censors use to differentiate between hate speech and legitimate political expression.

How to Protect Your Digital Privacy in the Era of Public Shaming

Americans face unprecedented threats to the digital safety of their personal information. We offer nine tips to foil hackers, ransomware, online trackers, data brokers and other menaces.

Breaking the Black Box: How Machines Learn to Be Racist

Artificial Intelligence is only as good as the patterns we teach it. To illustrate the sensitivity of AI systems, we built an AI engine that deduced synonyms from news articles published by different types of news organizations.

Breaking the Black Box: When Machines Learn by Experimenting on Us

As we enter the era of artificial intelligence, machines regularly conduct experiments on human behavior. Here’s a look at how software used by the New York Times and New York Post uses you to test their headlines.

When Algorithms Decide What You Pay

The phone you use, the computer you own and the ZIP code you live in can all be factors in what prices you see when shopping online. Welcome to the world of mass customization.

Breaking the Black Box: What Facebook Knows About You

We live in an era of increasing automation. But as machines make more decisions for us, it is increasingly important to understand the algorithms that produce their judgments.

Machine Bias

There’s software used across the country to predict future criminals. And it’s biased against blacks.

How We Analyzed the COMPAS Recidivism Algorithm

Meet the Online Tracking Device That is Virtually Impossible to Block

A new kind of tracking tool, canvas fingerprinting, is being used to follow visitors to thousands of top websites, from WhiteHouse.gov to YouPorn.