Popular hook-up app Tinder and dating sites OKCupid and PlentyofFish — all owned by online dating giant Match Group — don’t perform criminal background checks on their users, allowing convicted rapists and other registered sex offenders to roam freely, according to a new report.

While parent company Match Group performs background checks for its flagship site, Match.com, the other applications under the corporate umbrella put the burden on users to look out for themselves.

ProPublica published Monday an investigation into Match Group, the Dallas-based company that has a near-monopoly on online dating services and hook-up sites. The non-profit news organization found that the lack of a uniform background-check policy puts users at risk for sexual assault, with more than 150 such cases in recent years.

“There are definitely registered sex offenders on our free products,” a Match Group spokesperson told the publication.

In one instance, a 53-year-old divorcee used PlentyofFish to meet a 54-year-old man, with whom she went out on a few dates. A month after first meeting online, the man raped her. It turned out he was a three-time convicted rapist.

The ProPublica investigation analyzed the more than 150 incidents of alleged sexual assault involving dating apps, relying on news reports, civil lawsuits, and criminal records.

It found that most incidents occurred in the last five years and during the app users’ first in-person meeting. Almost all of the victims were women, who met their male attackers through Tinder, OkCupid, PlentyofFish, or Match.

Match Group is able to perform background checks on its paid Match.com subscribers, using state registries, according to the report.

But the company doesn’t take that step with its free products, including Tinder, because it doesn’t collect enough information from its free users and some paid subscribers, even when they pay for premium features.

Match Group declined to requests to interview executives. In a brief statement, the company told the publication that it “takes the safety, security and well-being of our users very seriously.”

The company said “a relatively small amount of the tens of millions of people using one of our dating services have fallen victim to criminal activity by predators,” adding that “we believe any incident of misconduct or criminal behavior is one too many.”

The report is the latest public-relations setback for Match Group. Earlier this year, a former Tinder executive filed a lawsuit alleging that the company’s CEO at the time sexually assaulted her and fired her following her complaint about the incident.

The FTC filed a complaint against Match.com in September, saying the site used fake accounts to lure almost 500,000 people to become paying subscribers.

Last year, founders of Tinder filed a lawsuit against Match Group and its then-parent company IAC/InterActiveCorp for allegedly manipulating financial information in a way that hurt Tinder’s valuation.

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