Broderick Group was in charge of leasing the project, at 320 108th Ave. N.E. Broderick said in its year-end Eastside report that the space had been taken by “an undisclosed tech tenant.”

Kidder Mathews says in its recent fourth-quarter report that the tenant is Amazon. Colliers said the same in its fourth-quarter report.

Neither Amazon nor Hines has yet issued a press release or confirmed those reports.

Designed by LMN, Summit III will be relatively quick to build, since the seven-level, 650-stall underground garage is already in place. It was built in 2009 by prior owner Bentall Capital, then paused by the recession.

Bentall sold the incomplete project, along with Summit I and II to Hines in 2015 for $320 million. (Bentall is the development arm of Canadian pension fund Ivanhoe Cambridge.)

Hines hasn’t announced a start date. JTM Construction will be the general contractor. The team also includes MKE, mechanical engineer; Berger Partnership, landscape architect; and Pace Engineering Services.

Amazon has a growing presence in downtown Bellevue. Last August it leased all of Expedia’s soon-to-be-vacated space in Tower 333, at 333 108th. That totals about 400,000 square feet. (Expedia will move to Seattle later this year.) And Amazon already occupies about 357,000 square feet at Centre 425, at 425 106th Ave. N.E.

All three buildings total about 1.1 million square feet.

Meanwhile, Vulcan is planning three towers at 117 106th Ave. N.E. (on the old Bellevue Plaza retail complex), with a possible 850,000 square feet. They are also subject to the usual rumors of Amazon interest.

Hines’ Summit I and II together have about 524,130 square feet in towers with 11 and 13 stories. At the time of the 2015 sale, they were almost 95 percent leased to tenants including New York Life Insurance, Perkins Coie, Puget Sound Energy and Sterling Savings Bank. As those leases naturally expire, Amazon could find further room to expand.

When Summit III is done, total parking capacity for the complex will reach almost 2,200 stalls.

The Hines complex is a five-minute walk to Bellevue Transit Center, where light rail service will begin in 2023.