SAN JOSE — A legendary developer has proposed a vast expansion of a tech campus that would add 1.5 million square feet of offices in north San Jose next to where Google has already leased several big office buildings, city documents show.

Five big office sites would sprout next to four office buildings that developer Peery Arrillaga has already leased to the search giant near the corner of North First Street and Brokaw Road, according to the city documents.

The new buildings in the tech complex would add 1.52 million square feet of offices to north San Jose, the documents that Peery Arrillaga has filed with the city show.

Five 10-story office buildings, along with five parking structures, would be built in this phase of the development, according to the municipal documents. The proposal is described as “preliminary.”

Each of the five offices would total roughly 303,000 square feet and the site plans indicate that a parking structure would be attached to each building.

Consistent with their decades-long custom, developers John Arrillaga and Richard Peery couldn’t immediately be reached for comment about the proposal. Palo Alto-based Peery Arrillaga is one of Silicon Valley’s most dominant and successful development firms.

Mountain View-based Google was asked to comment on its potential interest in the expansion area of the site.

Of particular interest is the new preliminary proposal from Peery Arrillaga envisions a somewhat larger campus than what was previously considered for the site.

If the new proposal is granted approval, the completed north San Jose development would total a head-spinning 2.25 million square feet — enough office space for more than 11,000 tech workers.

The currently approved plans would allow as much as 2.03 million square feet of offices.

The expanded development site would front on North First Street, Brokaw Road, Bering Road, Crane Court, and U.S. Highway 101.

In 2019, Google leased the first four office buildings in the project, in a deal that totaled 729,000 square feet of office space.

The five new buildings would be directly adjacent to the quartet of offices that Google has already rented.

It wasn’t immediately known what factors have prompted Peery Arrillaga to seek a larger campus in the wake of Google’s leases from the same development company of the adjacent offices.

Four Google tech hubs have begun to sprout in San Jose, a dramatic expansion by a world-renowned company that could translate into 30,000 new jobs — and perhaps many more, depending on the digital dynamo’s use of newly bought sites.

The most high profile enterprise by Google is the company’s game-changing Downtown West transit village. Google plans a transit-oriented neighborhood of office buildings, shops, restaurants, hotel facilities, entertainment hubs, cultural amenities, homes, and open spaces near the Diridon train station.

Yet it’s also clear that Google has its sights set on multiple expansion hubs beyond the downtown.

Google’s principal areas of interest outside of downtown have sprouted as a daisy chain of sites along or near the North First Street light rail line. These Google nests include the Peery Arrillaga-owned campus at First and Brokaw, which also is a short distance from San Jose’s increasingly busy airport.