In article , Doug
Miller wrote:

No.

"1.10 (a) The bat shall be a smooth, round stick not more than 2 3/4 inches
in
diameter at the thickest part and not more than 42 inches in length. The bat
shall be one piece of solid wood."

Maybe.

You edited, Doug...

1.10
(a) The bat shall be a smooth, round stick not more than 2 3/4 inches
in diameter at the thickest part and not more than 42 inches in length.
The bat shall be one piece of solid wood. *NOTE: No laminated or
experimental bats shall be used in a professional game (either
championship season or exhibition games) until the manufacturer has
secured approval from the Rules Committee of his design and methods of
manufacture.*

(emphasis mine)