regarding vessel

18:20 Mar 25, 2015 

(from client) the radar/vessel that is being acquired
Thanks for your help

18:19 Mar 25, 2015 

In this case, 'regarding' is a different part of speech, and means 'the target they are regarding'.

17:26 Mar 25, 2015 

As soon as a potential CPA/TCPA danger is calculated, an alarm sounds and the regarding target starts blinking and changes to red colour.
In this case 'regarding' seems to refer clearly to the target.
I am hoping to have more details tomorrow.

16:43 Mar 25, 2015 

Just that little bit of extra context now makes it abundantly clear that it does indeed mean 'the vessel doing the watching'

16:18 Mar 25, 2015 

My guess is it stands for "matching"/corresponding perhaps. I have asked the client naturally...
Other examples are:
To get congruence between radar image and the optical view at the radar display position, the regarding positions difference between radar antenna and display position must be set as distance values on an X/Y axis. This correction is content of the installation and setting into work procedure. The installation setting includes also the exact determination of antenna position in relation to ship's hull dimension.
Speed and course vectors have same colour like the regarding target symbols:

15:41 Mar 25, 2015 

It sounds on the face of it rather stilted — this could indicate a non-native writer, or simply be the result of patent-style language. What other clues do you have in the rest of your text?
I would have thought 'regarding' in the sense of 'obsreved/tracked' would be an unlikely interpretation, even if the writer were non-native.
I would supect the opposite: that the 'regarding vessel' means 'the vessel that is doing the tracking / observing'