NEW YORK (AP) ¿ Shares of Origin Agritech Inc. soared to their highest point in more than two years Monday, their fourth big jump over the past five trading days on extremely heavy volume.

On Nov. 21, Origin said the Chinese government issued a final approval for its genetically modified corn seeds.

The China-based hybrid seed developer said then it received a Bio-safety Certificate from the Chinese Ministry of Agriculture, paving the way for commercial introduction of its "phytase corn," which it says will help animal food producers cut down on feed costs.

The company said feed producers will now be able to skip purchasing phytase and corn separately and mixing them together.

Phytase increases phosphorus absorption in animals. It's a mandatory additive for animal feed in Europe, Southeast Asia, South Korea and Japan, Origin said.

Origin did not say when the corn would be available for sale.

Shares hit their highest point since Oct. 2007 at $12.62 earlier in the session before trading to $12.07 at midday. The stock has more than doubled since Nov. 21. Daily volume in the past five trading sessions has been in the tens of millions of shares.

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