Companies beginning with H:
H2 Creative Digital
H2 Partners
Habit5
Habu / Reveal Mobile - latter a location data specialist, rebranded and merged into Liveramp
Hahn Public
Hall & Partners
Hallett Arendt
Hansa Research Group
Happy Thinking People - acquired by Human8
Harte-Hanks
Healthcare Research Worldwide
Heap Analytics
Heart+Mind Strategies - web site blank except top bar 4/25
Hearts & Science
Heatmap
Heawood Research
Helixa
Hellebusch Research & Consulting, Inc.
Hellman & Friedman - investor, acquired Zendesk
Hello Ara
Hello Customer
HELM Digital
Hex Technologies
Hexa Research
HFS
HG Insights
Hi-Tech BPO
High Beam Global
HireRoad
Hispanic Research Inc.
Hivestack - research division is now part of Perion brand
Holden Healthcare
Hookit
Hope + Anchor
Horizon
Hotspex Inc
house51 Strategic Research - site not found 4/25
HowLikely - site 'under maintenance' 4/25
HR Acuity
Human8
Humanising Autonomy
Humankind
Humu
Huq industries
Huron