# Circleback funding: rounds and investors > Circleback has raised $15M across 2 rounds since 2015. Investors include Y Combinator, Pioneer Fund and Rebel Fund. Every round with its source. Source: https://millionrounds.com/company/circleback (Millionrounds; every figure on the page links to its filing or article) United States · [Seed startup](https://millionrounds.com/companies) # Who invested in *Circleback* 2 rounds we have observed, with the 8 investors named in them. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it. AI Funding summary Updated 26 Oct 2026 **$15M** raised across 2 rounds since 2015, from 2 sources **$12M** Venture **$2.5M** Seed - **Latest round:** Seed, $2.5M Nov 2024 - **Biggest round:** $12M Venture · Jul 2015 - **Investors:** 8 See who backed them ## The funding story Each circle is a round, placed by date and sized by amount. The line above is the running total. 2015 2017 2019 2021 2023 **$12M** Venture **$2.5M** Seed - **First round:** Venture, $12M - **Biggest round:** $12M - **Between rounds:** 9.3 years ## The rounds - **Nov 2024** Seed **$2.5M** *4 new* [Y Combinator](https://millionrounds.com/fund/y-combinator) [Pioneer Fund](https://millionrounds.com/fund/pioneer-fund-2) [Rebel Fund](https://millionrounds.com/fund/rebel-fund) [Transpose Platform Management](https://millionrounds.com/fund/transpose-platform-management) Source recorded - **Jul 2015** Venture **$12M** *4 new* [Grotech Ventures](https://millionrounds.com/fund/grotech-ventures) [TDF Ventures](https://millionrounds.com/fund/tdf-ventures) [Syncom Venture Partners](https://millionrounds.com/fund/syncom-venture-partners) [Clark Enterprises](https://millionrounds.com/fund/clark-enterprises) From a historical funding record ## Who was in which round The busiest backers across the latest rounds. A filled square is a round they joined; a dark one, a round they led. **Venture** 2015 **Seed** 2024 [Y Combinator](https://millionrounds.com/fund/y-combinator) [Pioneer Fund](https://millionrounds.com/fund/pioneer-fund-2) [Rebel Fund](https://millionrounds.com/fund/rebel-fund) [Grotech Ventures](https://millionrounds.com/fund/grotech-ventures) [Transpose Platform Management](https://millionrounds.com/fund/transpose-platform-management) [TDF Ventures](https://millionrounds.com/fund/tdf-ventures) [Syncom Venture Partners](https://millionrounds.com/fund/syncom-venture-partners) [Clark Enterprises](https://millionrounds.com/fund/clark-enterprises) ## Everyone who backed them [Y Combinator](https://millionrounds.com/fund/y-combinator) Accelerator **1** round [Pioneer Fund](https://millionrounds.com/fund/pioneer-fund-2) Private equity **1** round [Rebel Fund](https://millionrounds.com/fund/rebel-fund) VC firm **1** round [Grotech Ventures](https://millionrounds.com/fund/grotech-ventures) VC firm **1** round [Transpose Platform Management](https://millionrounds.com/fund/transpose-platform-management) VC firm **1** round [TDF Ventures](https://millionrounds.com/fund/tdf-ventures) VC firm **1** round [Syncom Venture Partners](https://millionrounds.com/fund/syncom-venture-partners) VC firm **1** round [Clark Enterprises](https://millionrounds.com/fund/clark-enterprises) Private equity **1** round Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=circleback). ## Also claim to have backed them These 2 firms list Circleback as a portfolio company on their own websites, but no report of a round names them. They are the firms' own claims, kept apart from the rounds above. [Phosphor Capital](https://millionrounds.com/fund/phosphor-capital) VC firm Per its own site [Entrepreneur Ventures](https://millionrounds.com/fund/entrepreneur-ventures) Corporate VC Per its own site ## Quick answers about Circleback ### Who invested in Circleback? Circleback's investors include Y Combinator, Pioneer Fund, Rebel Fund, Grotech Ventures and Transpose Platform Management, and 3 more on record. ### How much has Circleback raised? Circleback has raised $15M across 2 rounds since 2015. ### When did Circleback last raise? Circleback's most recent round was a Seed of $2.5M in Nov 2024. ### What was Circleback's biggest round? Circleback's largest round on record is $12M (Venture), in Jul 2015. ### Who backed Circleback first? Circleback's first round on record, in Jul 2015, was backed by Grotech Ventures, TDF Ventures and Syncom Venture Partners and 1 others. ### What stage is Circleback at? Circleback's latest named round is a Seed, in Nov 2024. ### Where is Circleback based? Circleback is based in the United States. ## Companies like Circleback In the same sector, and raised in the last eighteen months. [**SpaceX** $42B · Oct 2026](https://millionrounds.com/company/spacex)[**xPay** $1.5M · Oct 2026](https://millionrounds.com/company/xpay)[**Albert Invent** $20M · Oct 2026](https://millionrounds.com/company/albert-invent)[**FORT Robotics** $39M · Oct 2026](https://millionrounds.com/company/fort-robotics)[**Pika** $216M · Oct 2026](https://millionrounds.com/company/pika)[**Vertical Semiconductor** $84M · Oct 2026](https://millionrounds.com/company/vertical-semiconductor) ## Find investors like these Search every investor by what they have actually funded, then narrow to your stage and market. Free. Open the investor searchOr these rounds in the app