Zillow CEO Spencer Rascoff at the company's offices in Seattle.
Zillow CEO Spencer Rascoff at the company’s offices in the Russell Investments Center in Seattle.

Fast-growing Zillow may be getting a little more room for expansion at its downtown Seattle headquarters.

The Russell Investments Center building.
The Russell Investments Center building.

The online real estate powerhouse is eyeing an additional 115,000 square-feet of office space in the Russell Investments Center, the company’s home since 2011, sources tell GeekWire.

The new space — currently the home of struggling Seattle biotech company Dendreon, which filed for bankruptcy earlier this month — would represent a significant increase for Zillow, allowing it to accommodate about 600 new workers.

It is getting tougher for companies to find office space in Seattle, so Zillow’s expansion could simply be a competitive space grab to make sure it’s not left in the cold if the rapid growth continues. It also could come at a good time for the building owners, given Dendreon’s bankruptcy and that the building’s namesake, Russell Investments, is being sold to the London Stock Exchange Group.

Zillow has continuously gobbled up space in the 42-story building at 1301 Second Avenue, the former home of Washington Mutual. Zillow now occupies floors 29 to 34 in the skyscraper, and holds an option to take over floor 35 in the next few years. That space totals about 150,000 square feet.

Zillow Chief Marketing Officer Amy Bohutinsky said they have nothing to announce related to new office space.

Zillow employed just 300 people worldwide when it moved into the Russell Investments Center in August 2011, a number that has more than tripled to 1,099 as of September 30th. Much of that growth in headcount has come via acquisitions, with new offices in New York, San Francisco and Lincoln, Nebraska (home to Mortech, which Zillow purchased in 2012).

Zillow's common area where played host to the GeekWire Summit pre-party.
Zillow’s common area played host to the GeekWire Summit pre-party.

But Zillow also is growing organically as well, with plenty of new jobs available in its hometown. In fact, the company has 120 open positions in Seattle right now.

Zillow also will more than double in size if its $3.5 billion acquisition of San Francisco-based Trulia — owner of Bellevue-based Market Leader — goes through early next year. Trulia employed about 1,100 people at the time that the acquisition was announced, with the companies not saying whether layoffs will occur after the deal occurs.

Zillow CEO Spencer Rascoff did say at the time that the deal was announced that the company could achieve $100 million in cost avoidances in 2016 through things such as consolidation of advertising spending and new employee hiring.

Earlier today, GeekWire reported that Zillow and Trulia have set shareholder meetings for Dec. 18 to vote on the deal.

Zillow co-founder Rich Barton often talks about the need for entrepreneurs to “go big,” and it appears with the expansion plans that the Seattle company is very much looking to fulfill those promises.

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