Apparently, investors have learned from Lyft's disastrous trading debut, which saw the company's shares drop below their IPO price just a day later as investors finally questioned the wisdom of handing a company with no clear path to profitability a $25 billion valuation. To wit, following a leak published in WSJ last night, Pinterest, which is due to be the next 'hot' unicorn IPO, has set its IPO price range at $15 to $17 a share (or around $11 billion at the upper end). That's below its last private valuation of $21.54 a share - meaning that those who invested during the company's last fund-raising round will instantly lose money the moment the company goes public (barring an immediate run-up in the share price).

By contrast, the price range for Lyft's heavily oversubscribed IPO was repeatedly raised due to demand, setting the stock up for an embarrassing drop that triggered widespread ridicule in the financial press and might even lead to shareholder lawsuits. Of course, as was later revealed, Lyft's best-known backer, Carl Icahn, sold his $550 million stake before the IPO.

During its last private fundraising round, Pinterest was valued at $12 billion. The company is hoping to raise as much as $1.3 billion in the IPO.

Last month, Pinterest sped up the timing of its IPO timing to try and tap into the market while the "conditions" - that is, the torrid rally - last. The social network has more than 250 million active users who visit it to browse through billions of images.

It generates most of its revenue from ads. In recent years, the company has been growing its revenue and narrowing losses, with its net loss narrowing to $63 million last year from $130 million. Though it remains unprofitable.

Of course, as the valuation sugar high that pumped up Lyft's pre-IPO valuation fades, we imagine Pinterest's underwriters are looking into options for protecting their shareholders.

After Pinterest, this year's next big unicorn IPO is expected to be Uber Technologies, Lyft's vastly larger rival, could debut as soon as April, unless we see a stunning reversal in market conditions that prompts a rethink of the timing.