The phrase "ghost jobs" might sound like something from Halloween, but it refers to the practice of employers advertising vacancies that don't exist.

In some cases the positions may have already been filled, but in others the job might not have ever been available.

It's a real and continuing problem on both sides of the Atlantic.

Up to 22% of jobs advertised online last year were positions listed with no intent to hire, according to a study across the US, UK and Germany by recruitment software provider Greenhouse.

A separate UK study put the figure even higher, at 34%.

Meanwhile, the most recent official data from the US Bureau of Labor Statistics shows that while there were 7.2 million job vacancies back in August, only 5.1 million people were hired.

Why are firms posting ghost jobs, and what is being done to tackle the problem?

In the US, a jobhunting tech worker called Eric Thompson is making politicians in Washington DC increasingly aware of the issue.

In October of last year Mr Thompson, who has more than 20 years of experience in the tech sector, was made redundant from a start-up. He spent the following two months unsuccessfully applying for hundreds of jobs.

"I looked at everything under the sun, applying for positions at my current level, and ones that were more senior and junior," he says.

It dawned on Mr Thompson that some of the advertised jobs simply didn't exist. The experience led him to set up a working group calling for legislation to ban the practice of fake job adverts in the US.

Continuing to meet with members of the US Congress, he has led the formulation of proposed legislation called The Truth in Job Advertising & Accountability Act.

This calls for expiration dates for listings when hiring is paused or completed, auditable hiring records, and penalties for employers who post misleading or non-existent roles. Mr Thompson hopes that some members of Congress will sponsor the legislation.

He has also started a petition, which has so far generated over 50,000 signatures. Alongside the signatures, he says he receives messages from people describing how ghost jobs have chipped away at their confidence and impacted their mental health. Something he describes as "shameful".

The New Jersey and California state legislatures are also looking at banning ghost jobs.

The Canadian province of Ontario, is however, leading the way. As from 1 January companies will have disclose whether an advertised vacancy is actively being filled.

Ontario is also moving to tackle the separate recruitment issue of "ghosting", whereby companies don't reply to applicants. Firms in the province with more than 25 employees will now have to reply to someone they have interviewed with 45 days. However, they still won't need to contact anyone they didn't chose to interview.

Deborah Hudson, an employment lawyer based in Toronto, says she's already been approached by companies "trying to get it right". But she has concerns about how the rules will be enforced.

"My cynical side, after almost 20 years in this field, wonders how they're actually going to monitor and regulate this. I don't think the government has the resources to investigate, so employers may still get away with noncompliance. But if people run into problems, they can make a complaint and it will be looked into."

Elsewhere in Canada, and in the US and UK there is no legal requirement to reply to candidates. Nor are there any current moves in the UK to tackle either ghost jobs or recruitment ghosting.

Ailish Davies, a jobseeker from Leicester in the UK, says that being ghosted by the small firms and big corporations alike is "soul destroying".

She adds: "The amount of time I've spent putting effort into tailoring an application, to hear nothing back, it knocks you down."

Ms Davies, who has been working in marketing for more than 10 years, describes one occasion where a hiring manager asked for her availability for an interview, and after she replied, she never heard back.

"Employers should treat job seekers with more compassion because the current job market is not a nice place to be."

Jasmine Escalera is a career coach and recruitment expert based in Miami.

She first became aware of ghost jobs through the women she coached. "They kept seeing the same job posted again and again, and asking me if they should reapply.

"They were applying into a black hole. The morale of any job seeker gets crushed."

So why are companies posting ghost jobs? Dr Escalera's research suggests a variety of reasons.

"We surveyed hiring managers, and found some companies post positions to create a talent pool," she says. "It isn't that they don't want to hire, it's more they're not hiring immediately.

"Others, we found, were inflating numbers and trying to show their company is growing, even if it's not."

Dr Escalera adds that she has also heard examples of companies posting jobs to obtain and sell data.

Whatever the reason for the fake adverts, Dr Escalera cautions that it is giving governments a false picture of job markets, which has negative, real-world consequences.

"We use data to develop policy and understand what market trends look like, and so if that data is somehow skewed, then we're not able to create the policies or provide the support that job seekers and employees need right now," she says.

For jobhunters hoping to avoid ghost jobs, Dr Escalera advises that they try to network with hiring managers.

"You will know a position is real if you're having conversations with real humans who work at that organisations," she says.

But, she adds, you should also look for red flags. "If you see that a job is being posted multiple times during a certain time frame, or that the job posting has been open for a while, then it is possible the posting is staying open because the job is not intended to be filled."