Cancellation theorem in group theory (for direct product) says that if $B$ is a finite group and $A \times B \simeq A_1 \times B_1$ and $B \simeq B_1$ then $A \simeq A_1.$

Of course, if $B$ is not finite, the result is absurd, even for finitely presented groups (Here is an example by Steve)

I wonder whether the cancellation theorem holds for different products (in finite or infinite cases), such as semi-direct product, free product, fiber product over a given group, Zappa-Szep product (knit product), Wreath product.

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