SVB held $21bn of 'available for sale' bonds and $91bn of 'held to maturity' bonds on its balance sheet, that were actually only worth $19bn an $76bn respectively on a mark-to-market basis, which means a total unrecognised hole its in balance sheet of $17bn. SVB's total equity was only $16bn[1][2]
That means it didn't have a liquidity crisis, and it didn't have reserves in excess of it's liabilities, it had a solvency crisis, and it has more liabilities than it has assets (before even considering the haircut it's assets will suffer at liquidation prices).
The crux of the issue here is that, for many types of assets, banks are able to test whether they meet capital requirements based on the price they paid for the assets, rather than the price the assets are currently worth. So SVB was sailing along nicely whilst it's bond portfolio slipped further and further under water, and wasn't required to recapitalise when it should have done.
That means it didn't have a liquidity crisis, and it didn't have reserves in excess of it's liabilities, it had a solvency crisis, and it has more liabilities than it has assets (before even considering the haircut it's assets will suffer at liquidation prices).
The crux of the issue here is that, for many types of assets, banks are able to test whether they meet capital requirements based on the price they paid for the assets, rather than the price the assets are currently worth. So SVB was sailing along nicely whilst it's bond portfolio slipped further and further under water, and wasn't required to recapitalise when it should have done.
[1] https://ir.svb.com/financials/annual-reports-and-proxies/def... [2] https://www.wsj.com/articles/bond-losses-push-silicon-valley...