The $500 million fundraising would value the ride-hailing service between $6 billion and $7 billion, the source said.
A Lyft spokeswoman declined to comment.
Lyft‘s fundraising efforts have been ongoing for months, and the company retained Qatalyst Partners in part to assist them in raising a fresh round of cash, according to other sources with knowledge of the matter.
Larger ride-hailing competitors, Uber and Didi, have raised so much money that Lyft‘s options of finding new investors who can write big checks are quite limited.
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Uber is valued at about $70 billion and Didi’s valuation is about $35 billion after its merger withUber‘s China operations in August.