Internet Provider Security (IPS) tags are used by domain registrar to administer a domain name registration service and related Domain Name System (DNS) services. An IPS tag is the label that applies to each registrar that registers domains in the country-code top level domain "uk" and is required to transfer domain names from one registrar to another.
This text talks about a country-code domain that contains no numbers
This is true. The country code UK is only letters, no numbers
( z1 talk :ARG0 ( z2 text :mod ( z3 this ) ) :ARG1 ( z4 domain :mod ( z5 code :mod ( z6 country ) ) :ARG0-of ( z7 contain :ARG1 ( z8 number :polarity - ) ) ) )