### Instruction:

Extract the cause and effect entities from the following sentence:
The TMT observatory science data and metadata shall support enforcement of an 18 month (TBC) proprietary period after delivery to the PI

### Assistant:

VARIABLE: delivery to the PI
AND: and
CONDITION: proprietary period
KEYWORD: after
EFFECT_1: The TMT observatory science data
EFFECT_2: proprietary period
CAUSE_1: delivery to the PI
NOT_RELEVANT: (TBC)


### END
