Privacy statement

Last updated 20 October 2026 (added: the free check)

Who I am

D.V. Sysenko is the trade name of Danil Sysenko, a sole trader in the Netherlands. I measure which firms ChatGPT and Google's AI answers name, and I write to firms about what I found. Registered with the Dutch Chamber of Commerce (KvK) under number 42184908; address: Mathenesserweg 122B-01, 3026 HK Rotterdam. Questions about your data: danil@sysenko.com.

If I wrote to you without being asked

This section is the notice the GDPR (AVG, article 14) requires when personal data does not come from you directly.

• What I hold: your firm's name and website, the business email address I wrote to, and sometimes the name and role of a person at the firm. I also keep the date of each message and any reply.
• Where it comes from: your firm's own website, public directories that list your firm (for example IamExpat), public registers (the NVM member directory of estate agents and the AFM register of financial service providers), and public LinkedIn profiles. Kantoren in Nederland: uw gegevens komen van uw eigen website en uit openbare registers (NVM, AFM). The measurement itself comes from public AI answers to questions I wrote; those questions contain no personal data.
• Why: to tell a firm how AI assistants describe it, and to offer a paid check. The legal basis is legitimate interest (article 6(1)(f) GDPR). I use only contact details the firm itself publishes for business contact, such as the address or contact form on its website, never a guessed or private address.
• How long: up to 12 months after the last message between us. If you ask me not to write, I keep only your address and the date on a do-not-contact list, so that I never write to you again.
• Who else sees it: nobody buys or receives it. Mail goes through my mail providers (Zoho Mail in its EU data centre, and Gmail). The website runs on a server of Contabo, a German hosting company, in the EU.

Your rights

You can ask what I hold about you, ask me to correct or delete it, or object to it. Reply "no" to any of my messages, or write to danil@sysenko.com; I answer within a month and usually the same day. If you are unhappy with how I handle it, you can complain to the Dutch data protection authority, the Autoriteit Persoonsgegevens.

This website

No cookies, no analytics and no tracking scripts. The web server keeps a standard access log (IP address, page, time, browser) for 14 days, then deletes it. Links in my messages carry a short tag with your firm's name, so the log shows whether a page I sent was opened. I use that only to decide whether to write again.

The free check

On sysenko.com/free-check you can enter your firm's name, website, city and trade. I send five questions for that trade and city to ChatGPT, through the data provider DataForSEO, and show you which firms were named. The questions contain no personal data and not your firm's name.

• What is stored if you do not leave an email address: the firm name, website, city and trade you typed, and the answers, for 7 days, so that the same check is not run twice. Nothing identifies you. For the limit of a few checks per visitor per day I keep a counter next to a hash of your IP address that cannot be linked from one day to the next; it is deleted after two days. Your IP address itself is not stored by the check (the web server's ordinary access log, described above, still applies).
• What is stored if you leave an email address and tick the box: the address, the date and time of your consent, the version of the consent text you saw, a hash of your IP address (as proof of the consent), and the check itself, which is then kept as long as the address.
• What is stored if you ask for 15 minutes on screen and tick the box: your name, email address, the firm name as you typed it, the two moments you suggested, the date and time of your consent and the version of the consent text you saw, and the check itself, kept as long as the request. A short-lived counter (the same kind as above, without your IP address itself) limits how many requests one visitor can send per day. I use the details only to email you about this request.
• Why: to email you the full report, to fix a time when you asked for one, and afterwards to write to you about how AI assistants describe your firm and my paid check. The legal basis is your consent (article 6(1)(a) GDPR), which is also the permission Dutch law (Telecommunicatiewet, article 11.7) requires for such mail. The boxes are not ticked in advance, and the free check works without them.
• How long: up to 12 months after your last contact with me, or until you withdraw. After that the address is deleted. If you ask me to stop, I keep only the address on the do-not-contact list so that I never write to you again.
• How to withdraw or delete: reply "stop" to any message or write to danil@sysenko.com. I delete your address, your request and your check within a month, usually the same day.
• Who else sees it: DataForSEO receives the five questions (not your name, address or IP address). Nobody buys or receives your data. The check runs on the same Contabo server in the EU as this site.

Gratis check: zonder e-mailadres bewaar ik de ingevulde bedrijfsgegevens en de antwoorden 7 dagen, zonder iets wat u identificeert. Met e-mailadres en aangevinkt vakje bewaar ik het adres, het tijdstip van uw toestemming, de versie van de toestemmingstekst en een hash van uw IP-adres, tot 12 maanden na ons laatste contact of tot u zich afmeldt. Vraagt u om 15 minuten op het scherm, dan bewaar ik uw naam, e-mailadres, bedrijfsnaam, de twee momenten die u opgaf en het tijdstip en de versie van uw toestemming, onder dezelfde termijn; ik gebruik die gegevens alleen om u over dit verzoek te mailen. Afmelden of verwijderen: antwoord "stop" of mail danil@sysenko.com.

Clients

For a paid check or monitoring I keep your contact details, the questions we agreed and the answers collected, for as long as you are a client and as long as Dutch tax law requires for invoices (7 years).