From: Rick Jones <redacted>
Date: Thu, 28 Aug 2008 11:00:48 -0700

Earlier in the thread mention was made of financial services types.
If someone has knowledge of the (probably) arcane rules under which
they must operate it would be great to hear more.  Does some entity
like the SEC (Securities and Exchange Commission in the United
States) mandate some sort of timestamp for when the trading request
"arrives at the trading system" and do they define that "arriving at
the trading system" means?

The issue is the ordering of processing the requests.

So if request A arrived on interface 1 before request B arrived on
interface 2, the trade described in A should be performed before the
one in B.

This is not "arcance" as you seem to suppose it might be, but rather
pretty clear fair handling or requests sent between trading desks.