United States · Funded startup

Who invested in OpenX

6 rounds we have observed, with the 16 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.

IT Services

Funding summaryUpdated 26 Oct 2026

$76Mraised across 6 rounds since 2007, from 6 sources

$5.0MSeries A$16MSeries B$10MSeries C$20MSeries D$25MSeries E
Latest round
SecondaryJun 2015
Biggest round
$25MSeries E · Jan 2013
Investors
16
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.

20072009201120132015
$5.0MSeries A$16MSeries B$10MSeries C$20MSeries D$25MSeries E?Secondary
First round
Series A, $5.0M
Jun 2007
Biggest round
$25M
Series E · Jan 2013
Usual gap between rounds
20 months
the median of 5

The rounds

  1. Jun 2015
    SecondaryAmount undisclosed1 new

    From a historical funding record

  2. Jan 2013
    Series E$25M3 new6 returning

    Reported by sec.gov

  3. May 2011
    Series D$20M5 new

    Reported by techcrunch.com

  4. May 2009
    Series C$10M2 new4 returning

    Reported by techcrunch.com

  5. Jan 2008
    Series B$16M1 new4 returning

    Reported by thealarmclock.com

  6. Jun 2007
    Series A$5.0M4 new

    Reported by techcrunch.com

Founders and team

From OpenX's own website: 3 on the team.

  • Joel MeyerChief Technology Officer
  • Julie RooneyChief Privacy Officer and Deputy General Counsel
  • Mark LiaoChief Financial Officer

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.

Series A2007Series B2008Series C2009Series D2011Series E2013Secondary2015Index VenturesAccelFirst Round CapitalMangrove Capital PartnersSapphire VenturesO'Reilly AlphaTech VenturesSAP VenturesPresidio VenturesMitsui Global InvestmentDAG Ventures

Everyone who backed them

Index VenturesVC firm4rounds
AccelVC firm3rounds
First Round CapitalVC firm3rounds
Mangrove Capital PartnersVC firm3rounds
Sapphire VenturesVC firm2rounds
O'Reilly AlphaTech VenturesVC firm2rounds
SAP VenturesVC firm2rounds
Presidio VenturesCorporate VC2rounds
Mitsui Global InvestmentCorporate VC2rounds
DAG VenturesVC firm1round
Samsung Venture InvestmentVC firm1round
Aol VenturesCorporate VC1round
SharesPost Investment ManagementGrowth equity1round
yet2VenturesCorporate VC1round
Jonathan MillerAngel1round
Cyber CommunicationsInvestment firm1round

Missing a round, or an investor who was in one? Tell us.

Quick answers about OpenX

Who invested in OpenX?

OpenX's investors include Index Ventures, Accel, First Round Capital, Mangrove Capital Partners and Sapphire Ventures, and 11 more on record.

How much has OpenX raised?

OpenX has raised $76M across 6 rounds since 2007. One round did not disclose an amount, so the total is a floor.

When did OpenX last raise?

OpenX's most recent round was a Secondary in Jun 2015.

What was OpenX's biggest round?

OpenX's largest round on record is $25M (Series E), in Jan 2013.

Who backed OpenX first?

OpenX's first round on record, in Jun 2007, was backed by Index Ventures, First Round Capital and Mangrove Capital Partners and 1 others.

What stage is OpenX at?

OpenX's latest named round is a Secondary, in Jun 2015.

Where is OpenX based?

OpenX is based in the United States.

Companies like OpenX

In the same sector, and raised in the last eighteen months.

Chariot Claims$23M · Oct 2026Subeca$9.0M · Oct 2026FlexCompute$53M · Oct 2026Negosh$3.1M · Oct 2026StarLifter$4.0M · Oct 2026Litewave.AI$1.7M · Oct 2026

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