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Bolts with Threads Excluded

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What constitutes "threads excluded" for a high strength bolt.  Does the
start of the threads have to be a certain distance from the shear plane?
How about the taper?  The bolt I'm looking at as I write this has a roughly
1/8" long taper between the solid shank and the start of the threads.

The RCSC commentary says "Inclusion of some thread run-out in the plane of
shear is permissible".  Does "thread run-out" include the taper?   Another
reference, The Structural Steel Designers Handbook, states "It is common
practice to allow the last 1/8 in of vanish thread to extend across a single
shear plane".  Does "vanish thread" include the taper?

This comes up because a job I designed is under construction, and we noted
on the plans that all bolts were to be "threads excluded".  The first
handful of bolts that have been installed have a few threads plus the entire
taper inside the shear plane.  I am tempted to require that all threads,
including the taper, be outside the shear plane, however what I've read
indicates otherwise.  This decision could cause the Contractor, and
subsequently me, some grief as the Contractor has already ordered tens of
thousands of bolts.

Thanks in advance.

Chris Serroels
CH2M HILL/Sacramento