Comment by zenbane

The big problem is a retail broker shutting down trading to protect hedge funds who were short. Confirmed in Congressional Testimony: "NSCC examined the market activity and clearing member margin requirements to consider whether it would be appropriate to adjust or waive the capital premium charge, as permitted under the applicable rule. NSCC determined that the spike in market volatility, particularly in the so-called meme stocks, was a material contributor to elevated VaR charges for several clearing members, including most of those subject to capital premium charges. NSCC determined that it would be appropriate to waive the capital premium charge for all clearing members, using the discretion provided in the rule to reduce or waive this charge.4 Just after 9 a.m., prior to the market opening at 9:30 a.m., updated daily margin statements reflecting the waiver were released in NSCC’s portal and revised excess/deficiency notices were emailed to clearing members. All clearing members timely satisfied their clearing fund requirements...NSCC’s role in the market is a neutral one. It does not impose trading restrictions upon its clearing members or their customers, and it did not instruct any clearing member to impose restrictions during the market volatility events of late January." - https://www.dtcc.com/-/media/Files/PDFs/DTCC-Statement-Febru...