Making the UniQure IPO add up

FORTUNE — Dutch gene therapy company UniQure yesterday filed to raise $75 million in an U.S. IPO, with plans to list on the NASDAQ. Nothing too unusual in the registration document, except when it comes to the part about existing shareholders:

If you carry a few ones, you’ll notice that the percentage of shares beneficially owned there comes out to a magical 108.9% — and that doesn’t even include shares owned by company management and employees.

The explanation seems to be buried below in the small print, which suggests that Coller Capital doesn’t really hold 27.12 million shares. Instead, it directly holds only 5.45 million shares, while the remainder is a double-counting of shares held by Forbion (a venture capital firm in which Coller is an investor). That means Coller’s actual stake is closer to 9%, thus making the math work out properly.

UniQure CFO Piers Morgan says that the company was legally required to double-count the shares because Coller has both a direct and indirect positions (Forbion’s other limited partners are not listed).

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