On Monday, First Round Capital published a letter it sent to its limited partners about the state of startup investing. It was uncovered by Fortune's Dan Primack.

According to New York's top startup investing firm, things are looking a bit unstable in the private markets. Specifically, First Round Capital notes that every nine days last year, a new startup received a $1 billion+ valuation, and that some of these so-called "unicorn" companies will be exposed as frauds.

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