I contacted Leaseweb, here is their reply :
"
Thanks for contacting LeaseWeb. LeaseWeb has a policy banning illegal
distribution of copyrighted material.
In order to process copyright infringement claims, please ensure your
claim adheres to the Dutch Notice and Takedown Code of Conduct. This
means you have to first contact the infringing website, only if they do
not reply or their reply is unsatisfactory you can escalate to the
hosting provider. Please include a copy of your communication(s) with
the website when you file your claim again.
Failure to adhere to the Dutch Notice and Takedown Code of Conduct will
mean that we will request you to first contact the infringing website.
This will result in a considerable delay in processing your complaint.
As you have not indicated or proved you have tried to contact the
website please follow the procedure as described above, please allow 5
working days for a response from the website. If you have not received a
response after 5 days you can contact us again. Please provide proof you
contacted or tried to contact the website so we can process your claim
expeditiously.
If you have already done all the above, then please respond to this
message, so your ticket will open again, and you claim can be progressed.
Please do not forget to add the IP address of the abuse domain/link in
the complaint for fast progressing.
"
The FH developpers already have all the things needed. Don't be too kind with them.