Patent pool is in fact belonging to a hybrid governance structure between the market and contract, as well as shows a trend of diversification.

专利池实际上是介于市场与合同之间的混合制治理结构，日益呈现多元化趋势。

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The Absent Teacher Reserve pool was established in the 2005 teachers' contract, when forced job-placement within the school system ended.

WSJ: City Moving to Strengthen Teacher Pool

She said they should write a contract or even send e-mails confirming who took part in the pool and how much money they contributed.

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