Share story is negotiating to lease all of 635 Elliott Avenue West, a vacant Seattle waterfront office building that’s far afield from the technology giant’s South Lake Union headquarters campus, according to people familiar with the discussions.

Neither Amazon nor the building’s owner, Martin Selig Real Estate, responded to requests for comment Friday on the lease negotiations.

635 Elliott Avenue West, at the foot of Queen Anne Hill, hasn’t had a tenant since it was completed in 2010. But now it’s one of only two buildings north of the downtown core with empty contiguous space of more than 100,000 square feet, brokers say. The other is 5th & Bell, a building Amazon also is said to be close to leasing.

If the company follows through on 635 Elliott, it would be planting a flag some distance from Amazon’s sprawling South Lake Union-Denny Triangle nexus. But the company could be growing so fast that it can’t wait for new buildings to be completed, observers said.

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If Amazon is negotiating a lease at 635 Elliott, “It’s indicative of Amazon’s ongoing appetite to grow and find large blocks of contiguous space,” said Matt Christian, executive director at Cushman & Wakefield/Commerce in Seattle. “And they like the ability to control an entire building.”

Last year Amazon’s footprint in downtown expanded from 2.8 million to 3.2 million square feet, according to the Downtown Seattle Association.

An additional 4.7 million square feet of office space is in the pipeline for Amazon’s expansion, according to the association.

That includes Amazon’s 3.3 million-square-foot high-rise campus in Denny Triangle. Amazon also has long-term leases with Vulcan for almost 1 million square feet in new South Lake Union buildings slated for completion in 2015.

And according to people familiar with the matter, Amazon is close to leasing 5th & Bell and Blanchard Plaza, two office buildings near its future high-rise campus.

Adding 645 Elliott to the mix would be a coup for Selig, brokers said.

Selig built two four-story office buildings on the three-acre site: 645 Elliott on the north side and 635 Elliott on the south. The north building is two-thirds leased.

635 Elliott has just over 187,000 square feet of contiguous space, said Dan Dahl, senior vice president at Colliers International in Seattle.

If Amazon is negotiating a lease for the building, “It may be that they want to send a signal to the owners and developers in South Lake Union that they’re not locked in to South Lake Union,” he said.

“It certainly would be a boon for Mr. Selig and the whole Elliott corridor,” Dahl said. “This is the only large chunk of vacancy that he has, so this would be really great for him.”

In January, Amazon exercised an option to buy nearly an entire block in the Denny Triangle from Clise Properties, far ahead of the option’s expiration in December 2015, public records show.

Sanjay Bhatt: 206-464-3103 or On Twitter @sbhatt

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