Chinese crypto mining giant Bitmain’s filing to list its initial public offering (IPO) on the Hong Kong Stock Exchange (HKEx) will seemingly reach the end of its six-month expiration window today, as a crypto community member has noted in a tweet posted on March 25.

As the South China Morning Post has previously outlined, HKEx listing rules provide a six-month window for a given application to proceed to a closed-door hearing before its Listing Committee. The Committee is tasked with giving the final approval or disapproval of the offering; should an applicant fail to hear a response within this time frame, the listing formally lapses.

The filing — published in English and Chinese on Sept. 26, 2018 — thus appears to have reached the end of its validity window without confirmed reports of a Committee hearing, thus rendering the application obsolete.

The SCMP had also notably reported that HKEx was hesitant to approve the Bitmain listing, although the exchange’s representatives notably subsequently refuted this claim in correspondence with Cointelegraph.

Bitmain’s IPO listing plans had first come to light in June 2018, when erstwhile Bitmain CEO Jihan Wu revealed the firm was mulling an overseas IPO in a market with United States dollar denominated shares, such as Hong Kong.

Abundant speculation and controversies have since beset the endeavour, with investment analysts initially expecting the mining giant to raise anywhere from $3 billion to $18 billion, thereby potentially becoming the largest initial public offering in the IT market’s history.

By mid-summer, reports had surfaced of Bitmain allegedly sealing a IPO financing deal, bringing its valuation to $15 billion. Both Chinese tech conglomerate Tencent and Japan’s SoftBank — another tech giant whose 15 percent stake in Uber makes it the drive-hailing app’s largest shareholder — were purportedly involved.

In response to Cointelegraph’s investigations at the time, Softbank subsequently denied this alleged involvement. While Tencent eluded formal confirmation or denial, other purported investors soon likewise distanced themselves from rumored involvement.

Amid the protracted bear market, the IPO venture faced redoubled difficulties, with the extensive earnings disclosures that Bitmain submitted in line with the IPO listing requirements reportedly revealing that the firm was shouldering hefty losses during the market downturn.

In recent months, Bitmain has made several contractions of its global operations along with cuts to staff numbers, and is also fielding two class action lawsuits. This January, the firm reshuffled roles at its top executive level, with Jihan Wu and Micree Zhan Ketuan stepping aside as co-CEOs but continuing in the role of co-chairs.