14.9.1.2.2. Call Transfer 
- Transfer Talking (Attended transfer): no display update for any
device;
- Transfer Ringing (Semi attended transfer): offered at OS4K side;
not at Skype for Business side no display update for any device;
- Blind transfer: offered at Skype for Business side; not at OS4K
side Original Skype for Business call partner does not get a display
update. Transferred-To party gets Original Skype for Business partner's
name/number from Skype for Business in the initial call setup.
Functionality
The OS4K user can transfer calls to a Skype for Business party, Attended,
Semi attended (only on OS4K side) and blind (only on Skype for Business
side) transfer possible.
Attended transfer Display – no display update for any device –
CO behavior; Calling party will see after transfer called party name
and number and transfered to party will see calling party name and number
on first line display.
Semi attended transfer (only on OS4K side) Display – no display
update for any device – CO behavior; Calling party will see after transfer
called party name and number and transfered to party will see calling
party name and number on first line display
Blind transfer (only on Skype for Business side) Display – Transferred
pty's display is not updated; Calling party will see after transfer
called party name and number and transfered to party will see calling
party name and number on first line display