The stakes of Greylock Partners and New Enterprise Associates in Workday Inc. (NYSE: WDAY) soared as the cloud computing company completed the biggest tech IPO since Facebook.

Greylock Partners’ 10.90 percent stake swelled to $739.60 million, as Workday’s shares closed at $48.69 per share on Oct. 12, up 73 percent from the $28 offer price. The Silicon Valley venture firm with offices in Cambridge, Mass., owns 15.19 million shares.

NEA’s 10 percent stake rose to $678.73 million. The venture firm, with offices in Chevy Chase and Timonium in Maryland, owns 13.94 million shares.

Both venture firms, early investors in the Pleasanton, Calif., company, did not sell any shares in the IPO.

Workday, which makes cloud-based human resources software, raised $637 million by selling 22.75 million shares at $28 apiece. The company is valued at $4.50 billion.

Founded in 2004 by ex-PeopleSoft executives David Duffield and Aneel Bhusri, Workday’s clients include big tech companies such as Hewlett-Packard.