Trinseo Materials S. a r.l.

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Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933 (amendment)

Registration statement under Securities Act of 1933