HMC1122 issue

hi 

this is the block diagram of HMC1122, when I was testing this IC using multimeter 

I found that:

1. pin 5 and pin 6 are connected with package base GND.

2. pin 7,8 to pin 12 are connected together with pin 6 and pin 13 in DC.

3. pin 7,8 to pin 12 are NOT connected with package base in DC.

Is that normal or I have bought some fake IC?

Look forward for your reply,thank you.