BlackRock, an investor in Byju’s, estimates that its stake of Indian edtech giant, once valued at $22 billion, is now worth nothing. The write-down in its estimations, disclosed in an SEC filing, makes Byju’s one of the most spectacular startup slides in recent memory.

BlackRock’s disclosure for the period ending March this year follows a rough year for the Bengaluru-based startup, which was India’s most valuable startup not long ago. Byju’s struggled to meet its financial reporting deadlines last year, ultimately falling short of its revenue projections by more than 50% as it faced various governance issues.

Those issues — coupled with the abrupt resignations of its auditor and board members — contributed to derailing a $1 billion fundraise deliberation.

Prosus, one of Byju’s largest investors, publicly slammed the startup, alleging the company had “regularly disregarded advice” from it. Amid the funding crunch, the startup then raised $200 million at a post-money valuation of about $250 million this year – but the investment is being legally disputed by some of its largest investors.

So it doesn’t come as a surprise that BlackRock has implied a zero valuation to Byju’s. It’s not the first time the asset manager has marked down the valuation of Byju’s. At the end of October last year, BlackRock had cut the valuation of Byju’s to about $1 billion.

A BlackRock spokesperson declined to comment. Byju’s also declined to comment.

Separately, in a research note HSBC also estimated the value of Prosus’ 10% stake in the Indian startup to have diminished so severely, that its analysts have not bothered to attribute any value to it at all.

A spokesperson clarified in an email to TechCrunch after publication that HSBC was not attempting to value the whole company, just Prosus’ stake and that refraining from assigning a value is not equivalent to assigning a value of zero. However, the research’s note chart (embedded below) did use zero in the column for estimated value.

The bank also estimated that Prosus’ stake in a number of other startups — Meesho, Pharmeasy, ElasticRun, and Stack Overflow — are not nearly as valuable as they once were.

“We apply a 50% discount to the latest funding round/acquisition price for assets where the last round is older than six months to account for the recent correction in similar edtech/SaaS companies’ public sector multiples,” HSBC wrote in the note.

Correction: The story was updated to clarify HSBC’s valuation of Byju. The story has also been updated to emphasize BlackRock’s valuation adjustment in its Byju’s stake.