Bird is raising a Series D round led by Sequoia Capital at a $2.5 billion valuation, TechCrunch has learned. Sources, however, did not indicate the size of the round.

This round follows reports from The Information that Bird was looking to raise $200 million to $300 million by the end of this summer, at a post-money valuation of more than $2.3 billion.

Bird declined to comment on the funding round, saying it does not comment on rumors or speculation.

Sequoia Capital previously led Bird’s $300 million Series C round back in June, with Roelof Botha joining Bird’s board at the time. Sequoia declined to comment on the round, but Botha did say the Bird team “exemplifies grit.”

“What they’ve accomplished in achieving both rapid growth and strong unit economics is rare for a company this complex and so early on,” Botha said in an email to TechCrunch. “Bird’s innovation across a spectrum of disciplines to achieve operational excellence at scale, including hardware design and manufacturing, vehicle maintenance and repair, optimization of Bird charging and deployment, and city-level regulatory affairs is unparalleled.”

Last week, Bird CEO Travis VanderZanden said Bird has positive unit economics on its new Bird Zero scooters, which accounts for more than 75% of its fleet. But based on one of the images VanderZanden tweeted, it seems that figure is based on a period of four weeks in the summer when scooter ridership is likely higher.

In June, Bird acquired Scoot in a deal worth less than $25 million. That acquisition marked Bird’s first expansion into traditional bicycles and mopeds. Shortly before that, Bird unveiled a two-seater hybrid bike/moped vehicle called the Bird Cruiser. In addition to offering shared vehicles, Bird is also selling scooters directly to consumers.

Prior to this round, Bird had already raised more than $400 million in funding and reached a valuation of $2 billion last June.

*An earlier version of this story said the round had closed. Bird, however, is still finalizing the round with Sequoia. We regret the error.