He has been running Dropcontact since 2016. Before that, he ran national public health surveys for the French government. That is where the methodology behind the benchmarks published on this site comes from.
Before Dropcontact, Denis Cohen founded the survey institute Atoo. Three and a half years after it was created, Atoo won a 10 million euro framework contract through a public tender from INPES, the French National Institute for Prevention and Health Education, against the largest French institutes, in partnership with CNAMTS, INSERM and the Ministry of Health.
The first of those studies, the 2005 Health Barometer, remains one of the most ambitious public health surveys ever run in France. It was run by INPES in partnership with CNAMTS, INSERM, the French Ministry of Health and OFDT, and its results were published by Éditions INPES.
In 2004, he designed a mobile-only sampling method to correct a bias nobody was correcting: telephone surveys called landlines only and excluded 14 % of the population, younger, more urban, lower income. 47,310 numbers generated with the three French mobile operators, 3,842 respondents in an independent sample. Dual-frame sampling has since become a standard for representative telephone surveys.
30,514 people surveyed over 4 months, 192 interviewers, 21 supervisors.
Thirty-seven authors from INSERM, CNRS, InVS, OFDT, Irdes and universities in France, Canada and the United States, coordinated by a nine-member steering committee.
Run by INPES in partnership with CNAMTS, INSERM, the French Ministry of Health and OFDT, which also funded it.
574 pages, published by Éditions INPES, ISBN 978-2-9161-9201-7. Read the publication
Dropcontact enriches and verifies B2B contact data through proprietary algorithms, with no purchased or resold contact database, on infrastructure located entirely inside the European Union.
The benchmark this page refers to is also run and funded by Dropcontact, which is among the fifteen tools tested. Its method is published in full: 20,000 real contacts, three input columns only, every email found actually sent, and independent double entry to verify each company and domain pairing. See the benchmark of 15 email finders.
In October and November 2019, the CNIL, the French data protection authority, opened a formal audit of Dropcontact on its own initiative, decision 2019-168C. An online review, then a full day of on-site questioning at CNIL headquarters, with direct access to the databases, the information system and the source code. On 6 November 2020, its President, Marie-Laure Denis, notified the closure of the audit, with no sanction and no formal notice.
Most enrichment providers display a compliance badge. We know of no other one that has been audited by a data protection authority. For a DPO the difference is not cosmetic: the audit covered the actual processing, with the source code open to the auditors. The opt-out list mechanism Dropcontact put in place in 2018 was later turned into an official CNIL recommendation on 27 January 2022.
Denis Cohen posts on LinkedIn about B2B data quality, email deliverability and what vendor benchmarks leave out.
Denis Cohen on LinkedIn