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to buy (of a government, public agency, etc. from a private citizen); to purchase
to buy up (all of something)
国は住民から土地を買い上げた。
The government purchased land from residents.
余剰作物を買い上げて、機関が再配布した。
After buying up the surplus produce, the agency redistributed it.
今秋、省は組合から備蓄米を買い上げる予定だ。
This autumn, the ministry plans to buy up rice reserves from cooperatives.