Bounding Box around Grouped Items

[damientNSKG4]

Anyone know why these boxes around grouped items are so large? I looked online and the most common cause seems to be an item hanging out somewhere, but this group doesn't have one. 

[ToanDN]

Check the family for ref lines. 

[damientNSKG4]

How do I do that?

Thanks

[azad.Nanva]

dbl click on your family or use ths Edit Family when you select the family :

[seydauzun]

Hello @damientNSKG4 

One of these families is having a 'Strong reference plane' far away to original object. Within the family you can just change the function of the reference plane.

Or some lines, reference lines etc...