Companies beginning with O:
Oakdene Hollins
Oakham Research
Oasis PR
occams research
Ocient
Octopus Competitive Intelligence
Ocurate - acquired by FenixCommerce
Odin Answers
Ogury
Okendo
OKO
Okra
Olinger Group
OMB Research
OMBEA
Ometria
Omneky
Omnilytics - apparently closed 4/25
Omnisis Ltd
On Device
Onclusive
Onclusive
Oncofocus Solutions
One Minute to Midnight
OneMagnify
OnePoll
OnePulse
Online Market Intelligence (OMI)
Onswitch
Ookla
Op4G / Opinions 4 Good - suspended pending fraud allegations
Opeepl
Open Influence
Opendatasoft
OpenText
OpenVault
OpenWeb
Opiniator
Opinion Matters
Opinion Research Services
OpinionLab
OpinionRoute
Opinions LTD
Opinium
Opinyin
Opportune - owned by Wondrlab
Optimal Workshop
Optimizely
Optimove
Orange Sheep Research
ORB International
Orbee
Ormax Consultants Pvt.Ltd.
Outdoor Media Association (OMA)
OutPoint
Outsource Marketing
Outsource Research
OvationMR
Oxford Research International
Oxygen Brand Consulting
Oxynia Strategic Research