Alexandria Lands Cambridge’s Largest Office Lease Of The Year

Cambridge appears to be gaining momentum in the artificial intelligence race.

The city has struggled with high vacancy in its office and lab markets following the biotech downturn, but it has now landed two significant AI office leases this month — first with industry giant Anthropic and now with a growing local startup.

Autonomous software company Blitzy signed a five-year, 52K SF lease to expand its headquarters at One Kendall Square, it announced Thursday. The complex is owned by Alexandria Real Estate Equities, the life sciences property giant with a huge Cambridge portfolio.

The deal is the largest office lease signed in Cambridge this year, Blitzy said in a release, citing JLL, the brokerage firm that represented it.

Blitzy was founded in 2023 by a pair of Harvard Business School graduates, and in May it raised $200M at a $1.4B valuation. It now has more than 200 employees, and the new space is being designed to support an expansion to 300.

“We’re choosing to keep building where we were founded and making an investment in the future of the AI community here,” Blitzy co-founder and CEO Brian Elliott said in a statement.

“This lease gives us room to grow and represents an intentional bet on Cambridge,” he added.

One Kendall Square is the same complex where Alexandria landed another major AI lease earlier this month when Anthropic, the industry heavyweight behind AI assistant Claude, signed a 24K SF deal.

Alexandria owns more than 4.5M SF of life sciences and office space in Cambridge, according to its second-quarter earnings filings. It groups its properties into a series of “megacampuses,” with One Kendall Square and surrounding buildings comprising a 1.3M SF complex that was 86% occupied at the end of Q2, prior to the Anthropic and Blitzy leases.

Another nearby campus, Alexandria Technology Square, was 75% occupied, and earlier this week the firm proposed redeveloping the former Moderna headquarters there into affordable housing in exchange for additional development rights.

Alexandria sold a series of buildings in Cambridge and the surrounding area in 2023 and 2024 as the biotech boom fizzled out, and last month it sold four lab condominiums in Kendall Square for $45M.

The broader Cambridge market has suffered from high vacancy over the last few years. CBRE‘s second-quarter report estimated its lab vacancy at 28.7% and its office vacancy at 26.9%.

But the city still has the institutional anchors of Harvard University and MIT that made it a global hub for the biotech industry, and local leaders have hoped a similar ecosystem could evolve around the booming AI sector.

Greater Boston has trailed San Francisco and New York City in AI funding and office leasing in recent years, but Massachusetts has spent money to help make the state more competitive, and it appears to be making some progress.

AI companies have comprised more than 60% of new leasing volume across Cambridge this year, JLL said.

“It’s no mystery that the Cambridge office market has been particularly hard hit during the last 6 years, but the green shoots are there,” JLL Senior Managing Director Bryan Sparkes, who represented Blitzy in its lease, said in a statement.