[Shugart23]

I know I can double an opponent's 1X opening with a 4432 shape ( 2 being in Opponent's suit)….Under the new ACBL Rules, specifically IN FOURTH SEAT, can I open an artificial 2C showing 3 unknown suits which would include possibility of a 4432 shape (guaranteeing a 7+ card fit with partner somewhere) ? Thank you

[steve2005]

I don't see why guaranteeing a 7-card fit is important? You are always guaranteed a 7-card fit with partner no matter what your hand is.
This will depend on chart in effect.
Basic - no
Basic+-No. Says any natural opening allowed. Doesn't say quasi-natural which is what you bid describes. It also does not meet definition of 3-suiter.
Open - tells what is forbidden. Here is where is is tricky. There doesn't appear to be forbidden specifically. But you could have length in clubs so will require avg strength (especially if passable)
Open+ - appears to be the same as Open

[johnu]

I would say not allowed under Open(+) chart

Under disallowed opening bids:

10 An Artificial opening bid showing two suits, neither of which is known

[hrothgar]

Shugart23, on 2018-July-01, 07:27, said:

I know I can double an opponent's 1X opening with a 4432 shape ( 2 being in Opponent's suit)….Under the new ACBL Rules, specifically IN FOURTH SEAT, can I open an artificial 2C showing 3 unknown suits which would include possibility of a 4432 shape (guaranteeing a 7+ card fit with partner somewhere) ? Thank you

Have you read the new charts?
What do they say?

[Shugart23]

hrothgar, on 2018-July-01, 19:17, said:

Have you read the new charts?
What do they say?

I interpret it the same way Steve (above does)...I think it is allowed in Open if Average Strength