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TLD;DR
Name Collision Concerns Impede Delegation
ICANN hired firm Interisle Consulting to carry out an independent investigation
on the issues that may arise from new gTLDs that are identical to TLDs being
used on internal networks. The publishing of the report sparked a
community-wide debate that later became known as the Name Collision issue. The
firm reported at ICANN 47 that .home and .corp gTLDs were cause for serious
concern since those strings are widely in use by internal naming systems. In
response to the report, ICANN labeled the .home and .corp strings as "high
risk" and proposed that neither of the strings be delegated until it could be
proven that risk is low.[8] These two strings are currently severely delayed
and some community members guess they may never be delegated.
They hired a consulting firm.