Alphabet's Google (GOOGL) - Get Report unit is said to quietly be buying up properties in Silicon Valley as it looks to expand its presence in the area, just as rival Apple (AAPL) - Get Report is getting ready to open its new headquarters in Silicon Valley, CNBC reports.

Google has reportedly purchased 52 properties in Sunnyvale, CA. for about $820 million from real estate development partner CBRE.

Google said Monday that it has over 72,000 employees and needs room to expand to hire more workers in order to sustain its growth.

Alphabet shares fell 1.4% to $951.99 by Thursday's close.

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