One of the first times I encountered the ICO was over ten years ago when the The Privacy and Electronic Communications (EC Directive) Regulations 2003 first came in to force on 11th Dec 2003.
The reason was that telcos have to offer Anonymous Call Rejection (for which they may charge) and the mobile operators were not offering it.
I complained to OFCOM and the ICO and got nowhere. Basically, the end of the line was the ICO admitting they were not following the rules (i.e. they were breaking the law) but saying they would do nothing about it!
Sadly over 10 years on the story has not changed, with one of my customers just getting an answer from the ICO on the matter.
Their excuse (like they need one) is: "we are aware that automatic network-level call rejection is
currently not feasible on all categories of service (e.g. on mobile
Since when has "not feasible" been an excuse for not following the law. The mobile operators have had over 10 years to make it feasible and still done nothing. This is an EU wide requirement.
Think about that - 10 years was enough time to build the large hadron collider! The entire GSM mobile network was devised, specified and deployed in well under 10 years.
Obviously it is not only feasible but incredibly simple to add ACR as a service. Andrews & Arnold Ltd offer services on mobiles with ACR even, and this is being pointed out to the ICO to refute their bogus argument.
This is just another example of the ICO treating these laws as a total joke.