Jim Vincent wrote:
A quick survey: Since this aspect of the regs is somewhat open to
interpretation, is your local FAA person telling you that a transponder is
required? What is your personal policy and understanding of the reg? If
the consensus is that a transponder is required, should associations such as
the SSA for badges and the OLC ding accordingly?

I think 91.215(b) makes it pretty clear that a transponder is required:

(4) All aircraft in all airspace above the ceiling and within the
lateral boundaries of a Class B or Class C airspace area designated for
an airport upward to 10,000 feet MSL

Marc