Hong Kong (CNN Business) Alibaba put a price on its highly anticipated Hong Kong stock market debut on Wednesday, the world's biggest share sale of the year so far.

Alibaba BABA China's largest e-commerce company said it was issuing the new shares at 176 Hong Kong dollars ($22.50) each. That's equivalent to a discount of about 3% to's closing price in New York, where its stock has traded since 2014.

The price falls short of the 188 Hong Kong dollars Alibaba had set as a ceiling last week, but the transaction will still raise about $12.9 billion for the company, assuming its bankers exercise an option to buy some additional shares over the next month.

"Secondary listings are an art form, not an exact science," said Jeffrey Halley, senior market analyst for Asia Pacific at Oanda.

Alibaba wants to make sure its Hong Kong listing generates a lot of interest, so "they're pricing at a level where I'm 100% sure those shares are going to be a lot higher on the day," he added.

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