This was the finding of the case Patrick Breyer vs Germany in 2016

https://www.whitecase.com/publications/alert/court-confirms-...

  What makes a dynamic IP address personal data?

The CJEU decided that a dynamic IP address will be personal data in the hands of a website operator if:

there is another party (such as an ISP) that can link the dynamic IP address to the identity of an individual; and the website operator has a "legal means" of obtaining access to the information held by the ISP in order to identify the individual. On the facts, if the BRD has the legal power to compel the relevant ISP to disclose sufficient information to identify Mr Breyer, then Mr Breyer's IP address will be personal data in the hands of the BRD.

The CJEU also did not ask the specific question in that case - Were the BRD LIKELY to identify Mr Breyer? If this is something that you have never done before or will do in the future then it is not likely that you will try to identify someone by their IP.