The viral publisher Unilad, known for its commitment to student-friendly online “banter”, is facing insolvency proceedings following a demand from HM Revenue and Customs (HMRC) amid concerns over the future of the site’s Facebook-centric business model.

HMRC issued a winding-up petition against Unilad’s parent company in July, which is due to be heard at the high court next week. Such notices are usually issued when a business has failed to pay its taxes and the company could be liquidated unless it can come to an agreement.

“The situation with HMRC is being resolved swiftly,” said a spokesperson for Unilad, who declined to give any further information on the social media publisher’s financial position or why it was facing the demand from the taxman.

The British site is currently the fourth biggest publisher on Facebook, according to analysis service NewsWhip, attracting more interactions from readers than major news outlets such as the New York Times, MailOnline, and the BBC. It has continued to rise up the Facebook rankings in recent months despite the social network’s insistence it is changing its algorithm to push higher-quality news in people’s newsfeeds.

There are continued concerns over whether such social media-centric publishers can continue to thrive and build sustainable business models, especially while relying on native advertising – where the sites produce their own content such as branded video for advertisers.

A spokesperson for Unilad also declined to comment on claims that staff had recently been laid off by the site. There was also no response to suggestions that the company could struggle to pay the site’s original founder Alex Partridge following a lengthy court case regarding his right to a stake in the company.

Earlier this year Unilad co-chief executive Sam Bentley left the Manchester-based company following unspecific “allegations of historic misconduct made against the company”, with Unilad saying other staff had been disciplined as a result of an internal investigation.

The site began life as a viral Facebook page founded in 2010 by Partridge, an Oxford Brookes university student who coincidentally also founded its arch-rival LADbible. Unilad’s original incarnation was briefly shut down two years later after being held up as symptomatic of “lad culture” and facing a backlash over posts that made jokes about rape and homophobia.

The Unilad brand and its Facebook page were later reused for a new site launched in 2014 under the leadership of Liam Harrington and Bentley, who were both in their early 20s. The site’s main Facebook page currently has 40 million followers, who see a mix of lighthearted news stories, memes, and viral videos. On Wednesday afternoon stories include the “Terrifying moment worker discovers dozens of rats under concrete”, a video of a cow with three horns in Brazil, and a tribute post to the BBC series Peaky Blinders.

Harrington told the Guardian in 2016 that publishers such as his are “social enterprises that are catering to everyone” and in common with other male-focussed viral publishers, had toned down its more extreme and offensive content and increased the number of features on issues such as men’s mental health. It also has a variety of sites and Facebook pages covering tech, gaming, food, and sport and launched a longform documentary series on the “Dark side of Britain”.