Do not recognize commas, colons, periods etc. as a value break when pasting into a Linked Record that is Set to NOT "Allow Linking to Multiple Records"
Nate Montgomery @ SmartSuite
Values that contain punctuation will not be successful pasted into a Linked Record field even if the Linked Record has been set to only allow one value.
This makes it impossible to paste, bulk paste, automate any values that go into a linked record that contain ', . ; ;' set with only allow linking to one record.