Apple Inc. is moving some of its data to Google’s computing-on-demand service from Amazon.com Inc.’s, according to sources familiar with the deal, a major victory for the Alphabet Inc. unit in its battle against Amazon and Microsoft Corp. to sell cloud computing services to other companies.

Apple’s move is a sign that Google is making progress in the roughly $26 billion cloud computing market, in which corporate customers rent access to tech giants’ computers to store and process data.

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